Nail

Nail (pronounced neyl)

(1) A slender, typically rod-shaped rigid piece of metal, usually in many lengths and thicknesses, having (usually) one end pointed and the other (usually) enlarged or flattened, and used for hammering into or through wood, concrete or other materials; in the building trades the most common use is to fasten or join together separate pieces (of timber etc).

(2) In anatomy, a thin, horny plate, consisting of modified epidermis, growing on the upper side of the end of a finger or toe; the toughened protective protein-keratin (known as alpha-keratin, also found in hair) at the end of an animal digit, such as fingernail.

(3) In zoology, the basal thickened portion of the anterior wings of certain hemiptera; the basal thickened portion of the anterior wings of certain hemiptera; the terminal horny plate on the beak of ducks, and other allied birds; the claw of a mammal, bird, or reptile.

(4) Historically, in England, a round pedestal on which merchants once carried out their business.

(5) A measure for a length for cloth, equal to 2¼ inches (57 mm) or 1⁄20 of an ell; 1⁄16 of a yard (archaic); it’s assumed the origin lies in the use to mark that length on the end of a yardstick.

(6) To fasten with a nail or nails; to hemmer in a nail.

(7) To enclose or confine (something) by nailing (often followed by up or down).

(8) To make fast or keep firmly in one place or position (also used figuratively).

(8) Perfectly to accomplish something (usually as “nailed it”).

(9) In vulgar slang, of a male, to engage in sexual intercourse with (as “I nailed her” or (according to Urban Dictionary: “I nailed the bitch”).

(10) In law enforcement, to catch a suspect or find them in possession of contraband or engaged in some unlawful conduct (usually as “nailed them”).

(11) In Christianity, as “the nails”, the relics used in the crucifixion, nailing Christ to the cross at Golgotha.

(12) As a the nail (unit), an archaic multiplier equal to one sixteenth of a base unit

(13) In drug slang, a hypodermic needle, used for injecting drugs.

(14) To detect and expose (a lie, scandal, etc)

(15) In slang, to hit someone.

(16) In slang, intently to focus on someone or something.

(17) To stud with or as if with nails.

Pre 900: From the Middle English noun nail & nayl, from the Old English nægl and cognate with the Old Frisian neil, the Old Saxon & Old High German nagal, the Dutch nagel, the German Nagel, the Old Norse nagl (fingernail), all of which were from the unattested Germanic naglaz.  As a derivative, it was akin to the Lithuanian nãgas & nagà (hoof), the Old Prussian nage (foot), the Old Church Slavonic noga (leg, foot), (the Serbo-Croatian nòga, the Czech noha, the Polish noga and the Russian nogá, all of which were probably originally a jocular reference to the foot as “a hoof”), the Old Church Slavonic nogŭtĭ, the Tocharian A maku & Tocharian B mekwa (fingernail, claw), all from the unattested North European Indo-European ənogwh-.  It was further akin to the Old Irish ingen, the Welsh ewin and the Breton ivin, from the unattested Celtic gwhīnā, the Latin unguis (fingernail, claw), from the unattested Italo-Celtic əngwhi-;the Greek ónyx (stem onych-), the Sanskrit ághri- (foot), from the unattested ághli-; the Armenian ełungn from the unattested onogwh-;the Middle English verbs naile, nail & nayle, the Old English næglian and cognate with the Old Saxon neglian, the Old High German negilen, the Old Norse negla, from the unattested Germanic nagl-janan (the Gothic was ganagljan).  The ultimate source was the primitive Indo-European h₃nog- (nail) and the use to describe the metal fastener was from the Middle English naylen, from the Old English næġlan & nægl (fingernail (handnægl)) & negel (tapering metal pin), from the Proto-Germanic naglaz (source also of Old Norse nagl (fingernail) & nagli (metal nail).  Nail is a noun & verb, nailernailless & naillike are adjectives, renail is a verbs, nailing is a noun & vern and nailed is a verb & adjective; the noun plural is nails.

Nail is modified or used as a modifier in literally dozens of examples including finger-nail, toe-nail, nail-brush, nail-file, rusty-nail, garden-nail, nail-fungus, nail-gun & frost-nail.  In idiomatic use, a “nail in one's coffin” is a experience or event that tends to shorten life or hasten the end of something (applied retrospectively (ie post-mortem) it’s usually in the form “final nail in the coffin”.  To be “hard as nails” is either to be “in a robust physical state” or “lacking in human feelings or without sentiment”. To “nail one's colors to the mast” is to declare one’s position on something.  Something described as “better than a poke in the eye with a rusty nail” is a thing, which while not ideal, is not wholly undesirable or without charm.  In financial matters (of payments), to be “on the nail” is to “pay at once”, often in the form “pay on the nail”.  To “nail something down” is to finalize it. To have “nailed it” is “to perfectly have accomplished something” while “nailed her” indicates “having enjoyed sexual intercourse with her”.  The “right” in the phrase “hit the nail right on the head” is a more recent addition, all known instances of use prior to 1700 being “hit the nail on the head” and the elegant original is much preferred.  It’s used to mean “correctly identify something or exactly to arrive at the correct answer”.  Interestingly, the Oxford English Dictionary (OED) notes there is no documentary evidence that the phrase comes from “nail” in the sense of the ting hit by a hammer.

Double-headed nails.

Double-headed nails are used for temporary structures like fencing.  When the shaft is hammered in to the point where the surface of the lower head is flat against the surface of that into which it's being hammered, it leaves the upper head standing proud with just enough of the shaft exposed to allow a claw-hammer to be used to extract nail.  There is a story that as part of an environmental protest against the building or demolition of some structure (the tales vary), activists early one morning went to the temporary fencing around the contested site and hammered in all the double-headed nails.  This is believed to be an urban myth.

The sense of “fingernail” appears to be the original which makes sense give there were fingernails before there were spikes (of metal or any other material) used to build stuff.  The verb nail was from the Old English næglian (to fix or fasten (something) onto (something else) with nails), from the Proto-Germanic ganaglijan (the source also of the Old Saxon neglian, the Old Norse negla, the Old High German negilen, the German nageln and the Gothic ganagljan (to nail), all developed from the root of the nouns.  The colloquial meaning “secure, succeed in catching or getting hold of (someone or something)” was in use by at least the 1760; hence (hence the law enforcement slang meaning “to effect an arrest”, noted since the 1930s.  The meaning “to succeed in hitting” dates from 1886 while the phrase “to nail down” (to fix in place with nails) was first recorded in the 1660s.

Colors: Lindsay Lohan with nails unadorned and painted.

As a noun, “nail-biter” (worrisome or suspenseful event), perhaps surprisingly, seems not to have been in common use until 1999 an it’s applied to things from life-threatening situations to watching close sporting contests.  The idea of nail-biting as a sign of anxiety has been in various forms of literature since the 1570s, the noun nail-biting noted since 1805 and as a noun it was since the mid-nineteenth century applied to those individuals who “habitually or compulsively bit their fingernails” although this seems to have been purely literal rather than something figurative of a mental state.  Now, a “nail-biter” is one who is “habitually worried or apprehensive” and they’re often said to be “chewing the ends of their fingernails” and in political use, a “nail biter” is a criticism somewhat less cutting than “bed-wetter”.  The condition of compulsive nail-biting is the noun onychophagia, the construct being onycho- (a creation of the international scientific vocabulary), reflecting a New Latin combining form, from the Ancient Greek ὄνυξ (ónux) (claw, nail, hoof, talon) +‎ -phagia (eating, biting or swallowing), from the Ancient Greek -φαγία (-phagía).  A related form was -φαγος (-phagos) (eater), the suffix corresponding to φαγεῖν (phageîn) (to eat), the infinitive of ἔφαγον (éphagon) (I eat), which serves as aorist (essentially a compensator for sense-shifts) (for the defective verb ἐσθίω (esthíō) (I eat).  Bitter-tasting nail-polish is available for those who wish to cure themselves.  Nail-polish as a product dates from the 1880s and was originally literally a clear substance designed to give the finger or toe-nails a varnish like finish upon being buffed.  By 1884, it was being sold as “liquid nail varnish” including shads of black, pink and red although surviving depictions in art suggests men and women in various cultures have for thousands of years been coloring their nails.  Nail-files (small, flat, single-cut file for trimming the fingernails) seem first to have been sold in 1819 and nail-clippers (hand-tool used to trim the fingernails and toenails) in 1890.

Francis (1936-2025; pope 2013-2025) at the funeral of Cardinal George Pell (1941-2023), St Peter’s Basilica, the Vatican, January 2023.

The expression "nail down the lid" is a reference to the lid of a coffin (casket), the implication being one wants to make doubly certain anyone within can't possible "return from the dead".  The noun doornail (also door-nail) (large-headed nail used for studding batten doors for strength or ornament) emerged in the late fourteenth century and was often used of many large, thick nails with a large head, not necessarily those used only in doors.  The figurative expression “dead as a doornail” seems to be as old as the piece of hardware and use soon extended to “dumb as a doornail” and “deaf as a doornail).  The noun hangnail (also hang-nail) is a awful as it sounds and describes a “sore strip of partially detached flesh at the side of a nail of the finger or toe” and appears in seventeenth century texts although few etymologists appear to doubt it’s considerably older and probably a folk etymology and sense alteration of the Middle English agnail & angnail (corn on the foot), from the Old English agnail & angnail.  The origin is likely to have been literally the “painful spike” in the flesh when suffering the condition.  The first element was the Proto-Germanic ang- (compressed, hard, painful), from the primitive Indo-European root angh- (tight, painfully constricted, painful); the second the Old English nægl (spike), one of the influences on “nail”.  The noun hobnail was a “short, thick nail with a large head” which dates from the 1590s, the first element probably identical with hob (rounded peg or pin used as a mark or target in games (noted since the 1580s)) of unknown origin.  Because hobnails were hammered into the leather soles of heavy boots and shoes, “hobnail” came in the seventeenth century to be used of “a rustic person” though it was though less offensive than forms like “yokel”.

Nails and pins

Mug shot “pin” from TeePublic featuring Lindsay Lohan (b 1986, left), Donald Trump (b 1946; POTUS 2017-2021 and since 2025) and Paris Hilton (b 1981, right).  In this context, although the product really is “the badge”, the name was gained from the built-in pin supplied to secure the object to clothing.

As designs, a nail and a pin are similar, obviously differing only in scale but the function of each is different.  A nail’s primary purpose is to function as a structural fastener joining materials (most typically two or more pieces of wood) although there are specialized nails driven into substrate by impact (variously with hammers or nail guns (sometimes called “pin-nailers”, some of which are built to fire “panel pins” (very slender nails) or small “headless nails”).  A nail relies on friction and compression in the surrounding material for its holding strength.  Pins look like scaled-down nails but mostly are used for alignment, retention or pivoting, rather than structural load-bearing.  Because of their more delicate construction, pins often are inserted through specific-purpose, pre-existing holes and in many cases are intended to be temporary and are thus removable.  Visually, both nails and pins have heads (round, flat, clipped etc) and a tapered shank with a tip pointed for pointed tip for penetration (“snub-nosed” nails do exist but are rare) and both are designed slightly to deform the surrounding material when driven.  The most obvious difference is that a pin’s head is very small and some are spherical and made from plastic; they’re designed only to be pushed with finger-pressure rather than being hit with a hammer.  Although the term “pin” is used for some specialized devices used in building and engineering (dowel pin, pivot pin, gudgeon pin (also as wrist pin), roll pin, cotter pin etc), the word is most associated with the tailor’s pin (used mostly in textiles and usually clipped to “pin”).  In jewelry design and textiles there are also variants including the “lapel pin” and the fashion industry’s device of last resort, the “safety pin”.

Pinhead in publicity shot for Hellraiser III: Hell on Earth (1992).

Clive Barker's (b 1952) supernatural horror movie Hellraiser (1987) was based on his novella The Hellbound Heart (1986) and was a surprise hit, making it a franchise which has thus far spawned nine sequels, the most recent released in 2022.  The plot involved a mysterious puzzle box that, when opened, summoned the Cenobites, a group of extra-dimensional, sadomasochistic beings unable to differentiate between pain and pleasure.  It was a good premise for a horror movie but the character who really captured the audience's imagination was the unnamed figure viewers dubbed “Pinhead”.  Although Pinhead appeared in the original film for fewer than ten minutes, the character became the franchise’s focal point and has since dominated the publicity material for subsequent releases.  The popularity of Hellraiser has been maintained and it’s hoped that for the next release the producers will offer the part to Peter Dutton (b 1970; leader of the Liberal Party of Australia 2022-2025).

Peter Dutton captured by a photographer during a happy moment (left), Pinhead with the box able to summon the Cenobites (centre) and and artist's depiction of Mr Dutton in “Pinhead mode” (digitally altered image, right).

No longer burdened with tiresome parliamentary duties since losing his seat in the 2025 Australian general election, Mr Dutton has time for a third career and he should be good at playing an unsmiling character who speaks in a relentless monotone; really, all he need do is act naturally.  It’s suspected also he’ll be good at learning a script given the decades he spent parroting “talking points” and TWS (three word slogans).  While it’s an urban myth Mr Dutton wasn’t offered the part of Lord Voldemort in the Harry Potter movie franchise because he was deemed “too scary”, as Pinhead he’d be “just scary enough”.  While the LNP (Liberal National Party) state government in Queensland recently has appointed Mr Dutton to the board of the QIC (Queensland Investment Corporation, the investment manager of the state’s Aus$135 billion in assets), it’s understood his duties in the Aus$130,000 per annum role will be neither onerous or time-consuming so there’ll be ample opportunity for film-shoots.  Although when in opposition the LNP had decried the ALP (Australian Labor Party) government’s frequent appointment of ALP figures to lucrative sinecures, once in office the LNP continued the “jobs for the boys” tradition.  In the modern era, the two most striking characteristics of right-wing fanatics is (1) a fondness for sitting safely in a bunker while advocating for (and sometimes sending) other people's children to go a fight a war somewhere and (2) after a career spent extolling the virtues of “private enterprise” and criticizing “government waste”, being anxious to get back on the public payroll as soon as their political careers end.  Reassuringly for taxpayers who may have been worried Mr Dutton would not be able to continue to enjoy the lifestyle to which their taxes made him accustomed (“entitled” as he might have put it), it’s believed his director’s fees from QIC will not affect his parliamentary pension (understood to be between Aus$260,000-Aus$280,000 per annum).

The Buick Nailhead

In the 1930s, the straight-8 became a favorite for manufacturers of luxury cars, attracted by its ease of manufacture (components and assembly-line tooling able to be shared with those used to produce a straight-6), the mechanical smoothness inherent in the layout and the ease of maintenance afforded by the long, narrow configuration, ancillary components readily accessible.  However, the limitations were the relatively slow engine speeds imposed by the need to restrict the “crankshaft flex” and the height of the units, a product of the long strokes used to gain the required displacement.  By the 1950s, it was clear the future lay in big-bore, overhead valve V8s although the Mercedes-Benz engineers, unable to forget the glory days of the 1930s when the straight-eight W125s built for the Grand Prix circuits generated power and speed Formula One wouldn’t see until the 1980s, noted the relatively small 2.5 litre (153 cubic inch) displacement limit for 1954 and conjured up a final fling for the layout.  Used in both Formula One as the W196R and in sports car racing as the W196S (better remembered as the 300 SLR) the new 2.5 & 3.0 litre (183 cubic inch) straight-8s, unlike their pre-war predecessors, solved the issue of crankshaft flex (the W196's redline was 9500 compared with the W125's 5800) by locating the power take-off at the centre, adding mechanical fuel-injection and a desmodromic valve train to make the things an exotic cocktail of ancient & modern (on smooth racetracks and in the hands of skilled drivers, the swing axles at the back not the liability they might sound).  Dominant during 1954-1955 in both Formula One & the World Sports Car Championship, they were the last of the straight-8s in top-line competition.

Schematic of Buick “Nailhead” V8, 1953-1966.

Across the Atlantic, the US manufacturers also abandoned their straight-8s.  Buick introduced their overhead valve (OHV) V8 in 1953 but, being much wider than before, the new engine had to be slimmed somewhere to fit between the existing inner-fenders (it would not be until later the platform was widened).  To achieve this, the engineers narrowed the cylinder heads, compelling both a conical (the so-called “pent-roof”) combustion chamber and an arrangement in which the sixteen valves pointed directly upwards on the intake side, something which not only demanded an unusual pushrod & rocker mechanism but also limited the size of the valves.  So, the valves had to be tall and narrow and, with some resemblance to nails, they picked up the nickname “nail valves”, morphing eventually to “nailhead” as a description of the whole engine.  The valve placement and angle certainly benefited the intake side but the geometry compromised the flow of exhaust gases which were compelled by their anyway small ports to make a turn of almost 180^o on their way to the tailpipe.  As an indication of the heat-soak generated by that 180^o turn, the surrounding water passages were very wide. 

It wasn't the last time the head design of a Detroit V8 would be dictated by considerations of width.  When Chrysler in 1964 introduced the 273 cubic inch (4.5 litre) V8 as the first of its LA-Series (that would begat the later 318 (5.2), 340 (5.5) & 360 (5.9) as well as the V10 made famous in the Dodge Viper), the most obvious visual difference from the earlier A-Series V8s was the noticeably smaller cylinder heads.  The A engines used as skew-type valve arrangement in which the exhaust valve was parallel to the bore with the intake valve tipped toward the intake manifold (the classic polyspherical chamber).  For the LA, Chrysler rendered all the valves tipped to the intake manifold and in-line (as viewed from the front), the industry’s standard approach to a wedge combustion chamber.  The reason for the change was that the decision had been taken to offer the compact Valiant with a V8 but it was a car which had been designed to accommodate only a straight-six and the wide-shouldered polyspheric head A-Series V8s simply wouldn’t fit.  So, essentially, wedge-heads were bolted atop the old A-Series block but the “L” in LA stood for light and the engineers wanted something genuinely lighter for the compact (in contemporary US terms) Valiant.  Accordingly, in addition to the reduced size of the heads and intake manifold, a new casting process was developed for the block (the biggest, heaviest part of an engine) which made possible thinner walls.  "Light" is however a relative term and the LA series was notably larger and heavier than Ford's "Windsor" V8 (1961-2000) which was the exemplar of the "thin-wall" technique.  This was confirmed in 1967 when, after taking control of Rootes Group, Chrysler had intended to continue production of the Sunbeam Tiger, by then powered by the Ford Windsor 289 (4.7 litre) but with Chrysler’s 273 LA V8 substituted.  Unfortunately, while 4.7 Ford litres filled it to the brim, 4.4 Chrysler litres overflowed; the Windsor truly was compact.  Allowing it to remain in production until the stock of already purchased Ford engines had been exhausted, Chrysler instead changed the advertising from emphasizing the “…mighty Ford V8 power plant” to the vaguely ambiguous “…an American V-8 power train”.

322 cubic inch Nailhead in 1953 Buick Skylark convertible (left) and 425 cubic inch Nailhead in 1966 Buick Riviera GS (with dual-quad MZ package, right).  Note the “Wildcat 465” label on the air cleaner, a reference to the claimed torque rating, something most unusual, most manufacturers using the space to advertise horsepower or cubic inch displacement (CID).

The nailhead wasn’t ideal for producing top-end power but the design did generate prodigious low-end torque, something much appreciated by Buick's previous generation of buyers who much had relished the low-speed responsiveness of the famously smooth straight-8.  However, like everybody else, Buick hadn’t anticipated that as the 1950s unfolded, the industry would engage in a “power race”, something to which the free-breathing Cadillac V8s and Chrysler’s Hemis were well-suited.  For that, the somewhat strangulated Buick Nailhead was not at all suited and to gain power the engineers were compelled to add high-lift, long-duration camshafts which enabled the then magic 300 HP (horsepower) number to be achieved but at the expense of smoothness; tales of Buick buyers (long accustomed to straight-8s that ran so smoothly at idle it could be hard to tell if the things were running) returning to the dealer to fix the “rumpity-rump” became legion.  Still, the Nailhead was robust, relatively light and offered what was then a generous displacement and the ever inventive hot-rod community soon worked out the path to power was to use forced induction and invert the valve use, the supercharger blowing the fuel-air mix into the combustion chambers through the exhaust ports while the exhaust gases were evacuated through the larger intake ports.  Thus, for a while, the Nailhead enjoyed a role as a niche player although the arrival in the mid 1950s of the much more tuneable Chevrolet V8s ended the vogue for all but a few devotees who continued use well into the 1960s.  Buick acknowledged reality and, unusually, instead of following the industry trend and drawing attention to displacement & power, publicized their big torque numbers, confusing some (though probably not Buick buyers who were a loyal crew who sometimes would look down on more expensive Cadillacs because they were "flashy").  The unique appearance of the old Nailhead retains some nostalgic appeal for the modern hot-rod community and they do sometimes appear, a welcome change from the more typical small-block Fords or Chevrolets.

Lockheed SR-71 Blackbird (1964-1999).

Not confused about numbers was the USAF (United States Air Force) which was much interested in power for its aircraft but also had a special need for torque on the tarmac and briefly that meant another quirky niche for the Nailhead.  The Lockheed SR-71 Blackbird (1964-1979) was a long-range, high-altitude supersonic (Mach 3+) aircraft used by the USAF for reconnaissance between 1966-1998 and by the NASA (National Aeronautics & Space Administration) for observation missions as late as 1999.  Something of a high-water mark among the extraordinary advances made in aeronautics and materials construction during the Cold War, the SR-71 used Pratt & Whitney J58 turbojet engines which featured an innovative, secondary air-injection system for the afterburner, permitting additional thrust at high speed.  The SR-71 still holds a number of altitude and speed records and Lockheed’s SR-72, a hypersonic unmanned aerial vehicle (UAV) is said to be in an “advanced stage” of design and construction although whether any test flights will be conducted before 2030 remains unclear, the challenges of sustaining in the atmosphere velocities as high as Mach 6+ onerous given the heat generated and stresses imposed by the the fluid dynamics of air at high speed.

Drawing from user manual for AG330 starter cart (left) and AG330 starter cart with dual Buick Nailhead V8s (right).

At the time, the SR-71 was the most exotic aircraft on the planet but during testing and early in its career, just for the engines to start it relied on a pair of even then technologically bankrupt Buick Nailhead V8s.  These were mounted in a towed cart and were effectively the turbojet’s starter motor, a concept developed in the 1930s as a work-around for the technology gap which emerged as the V12 aero-engines became too big to start by hand but lacked on-board electrical systems to trigger ignition.  The two Nailheads were connected by gears to a single, vertical drive shaft which ran the jet up to the critical speed at which ignition became self-sustaining.  The engineers chose the Nailheads after comparing them to other large displacement V8s, the aspect of the Buicks which most appealed being the torque generated at relatively low engine speeds, a characteristic ideal for driving an output shaft, torque best visualized as a "twisting" force.  After the Nailhead was retired in 1966, later carts used Chevrolet big-block V8s but in 1969 a pneumatic start system was added to the infrastructure of the USAF bases from which the SR-71s most frequently operated, the sixteen-cylinder carts relegated to secondary fields the planes rarely used.

Janus

Janus (pronounced jey-nuhs)

(1) In Roman mythology, a god of doorways (and thus also of beginnings), and of the rising and setting of the sun, usually represented as having one head with two bearded faces back to back, looking in opposite directions, historically understood as the past and the future.

(2) When used attributively, to indicate things with two faces or aspects; or made of two different materials; or having a two-way action.

(3) In zoology, a diprosopus (two-headed) animal.

(4) In chemistry, used attributively to indicate an azo dye with a quaternary ammonium group, frequently with the diazo component being safranine.

(5) In astronomy, a moon of the planet Saturn, located just outside the rings.

(6) In figurative use, a “two-faced” person; a hypocrite.

(7) In numismatics, (as Janus coin),a coin minted with a head on each face.

(8) In architecture, as the jānus doorway, a style of doorway, archway or arcade, the name derived from the Roman deity Iānus (Janus) being the god of doorways.

Mid-late 1500s: From the Latin Iānus (the ancient Italic deity Janus), to the Romans of Antiquity, the guardian god of portals, doors, and gates; patron of beginnings and endings.  The Latin Iānus (literally “gate, arched passageway”) may be from the primitive Indo-European root ei- (to go), the cognates including the Sanskrit yanah (path) and the Old Church Slavonic jado (to travel).  In depictions, Janus is shown as having two faces, one in front the other in back (an image thought to represent sunrise and sunset reflect his original role as a solar deity although it represents also coming and going in general, young and old or (in recent years) just about anything dichotomous).  The doors of the temple of Janus were traditionally open only during the time of war and closed to mark the end of the conflict, the origins of allusions to the “temple of Janus” being used metaphorically to mean conflict or wartime and the month of January is named after Janus, the link being to “the beginning of the year”.  The most commonly used forms are Janus-faced & Janus-headed while specialized uses include Janus cat (a cat with diprosopus (a condition in which part of the face is duplicated on the head)) and Janus particle (in nanotechnology and physics, a spherical microscopic particle which has hemispheres with sharply differing properties, such as one hydrophilic hemisphere and one hydrophobic hemisphere).  Janus is a noun or proper noun and Janus-like, janian, janiform & januform are adjectives.

Prosthetic in studio (left), Ralph Fiennes (b 1962) on-set in character (centre) and Peter Dutton (b 1970; leader of the opposition and leader of the Liberal Party of Australia 2022-2025) imagined in the same vein (right).

The prosthetic used in the digitally-altered image (right) was a discarded proposal for the depiction of Lord Voldemort in the first film version of JK Rowling's (b 1965) series of Harry Potter children’s fantasy novels; it used a Janus-like two-faced head.  It's an urban myth Peter Dutton auditioned for the part when the first film was being cast but was rejected as being "too scary" but if ever there's another film, the producers could do worse than to cast him and should Mr Dutton not resume his political career (God forbid), he could bring to Voldemort the sense of menacing evil the character has never quite achieved, fine though Mr Fiennes' performance surely was.

Peter Dutton captured by a photographer during a happy moment (left), Pinhead the head Cenobite (centre) and and artist's depiction of Mr Dutton in “Pinhead mode” (digitally altered image, right).

However, even if too scary to be a Voldemort, for the next instalment in the Hellraiser franchise, Mr Dutton may be just scary enough to be the next “Pinhead”, the leader of the Cenobites, extra-dimensional, sadomasochistic creatures unable to differentiate between pain and pleasure.  As well, as looking the part, to depict a convincing Cenobite, Mr Dutton would absorb little of the director’s time in rehearsals because he’d need just to “act naturally”.  The first Hellraiser film was released in 1987 and there have since been nine sequels with Pinhead gaining a cult following among aficionados of the genre so, should he need a post-political career, definitely he should audition.  Interestingly, despite many opportunities, Mr Dutton has never denied being a Freemason and that also would work in his favour because it’s clear the Cenobites are a Masonic crew.

Roman cast bronze coin from the aes grave series, circa 225-217 BC; it shows the bearded head of Janus opposite the prow of a war galley.

In the lushly populated pantheon of Roman gods, Janus (Iānus) was one of the oldest, represented with two faces, one looking forwards and the other backwards (ie artistically, to the left & right).  In some of the myths, Janus was a native of Rome where, at some point, he ruled with Camesus while others claimed he came from Thessaly and ended up in Rome as an exile, welcomed there by Camesus, who shared his kingdom with him.  He ruled alone after the death of his host and in many tales Janus built a city on a hill (consequently called Janiculum as would have been the convention).  He had come to Italy with his wife (Camasenea or Camise) and the best known of their children was Tiberinus.  Janus received Saturn when he was driven from Greece by Jupiter, Saturn ruling over Saturnia, a village situated on the heights of the capitol.  By consensus, it seems that during the reign of Janus people unfailingly were honourable & honest (the stories from Antiquity are well-named as “myths”) and there was universal peace and prosperity.  While trade was as old as humanity and it’s clear there had been various means of exchange, it’s Janus who is credited with inventing “money” in the modern sense in which currency is understood, the oldest known Roman bronze Roman coins cast with an effigy of Janus on one side and the prow of a boat on the reverse.  Where the myth-tellers differ is whether the “civilizing” of the first natives of Latium can be attributed to Janus or Saturn but upon his death he was deified so there was some sense of gratitude.

The fate of Tarpeia, pressed (bludgeoned in some stories) to death by the shields of the Sabines.

In the way the myths did tend to multiply, other legends became attached to his memory, the most famous being the events which transpired after Romulus and his companions had carried off the Sabine women, prompting Titus Tatius and the Sabines to attack the city.  One night, driven by her lust for Tatius, the treacherous Tarpeia delivered the citadel into the hands of the Sabines but rather than wedding her as he had promised, Tatius had her put to death on the very Roman basis: “nobody likes a snitch”.  His soldiers had already scaled the heights of the Capitol when Janus launched a jet of hot water which put them to flight; to commemorate this military miracle, it was decreed that in time of war the door of the Temple of Janus should always be left open so in times of trouble the god could come to the aid of the Romans.  It was closed only if the Roman Empire was at peace.  Janus was said also to have married the Nymph Juturna who gave him a son, the god Fontus (or Fons).

(John) Foster Dulles (1888–1959; US Secretary of State 1953-1959, left) with Dwight Eisenhower (1890-1969; US POTUS 1953-1961, right), Washington DC, 1955.

The terms “Janus-faced” or “Janus-headed” are used in engineering an architecture to describe designs where the “face” or “head” of an object or shape is duplicated but the idea usually is applied to people.  To speak of someone as being “two faced” is to suggest, variously, they’re deceitful, duplicitous or hypocritical.  Many have been damned (and sometimes even admired) as “two-faced” but on one occasion, after someone had observed Foster Dulles was “a bit two-faced” about something, Winston Churchill (1875-1965; UK prime-minister 1940-1945 & 1951-1955) responded he couldn’t be because “…if he had two faces, he wouldn’t use that one.”  During his not infrequent criticisms of Dulles, habitually Churchill would speak of his “great slab of a face” although in retirement the old enmities (mostly) were forgotten and in May 1959 he visited him in his hospital room in Washington DC.  The two had “a pleasant chat” and within a fortnight Dulles was dead.

Noses down: In the Berghof on the Obersalzberg on 21 June 1939, Albert Speer (1905–1981; Nazi court architect 1934-1942; Nazi minister of armaments & war production 1942-1945, (left) and Adolf Hitler (1889-1945; Führer (leader) and German head of government 1933-1945 & head of state 1934-1945, right) study plans for Linz's new opera house (photograph by Heinrich Hoffmann (1885–1957; Nazi court photographer), Bavarian State Library's Fotoarchiv Hoffmann.

Sometimes, such realizations, literal or figurative, come too late.  In the entry Speer made on 30 November 1946 in his clandestine prison diary (Spandauer Tagebücher (Spandau: The Secret Diaries) (1975)) is the passage: “Once again I am obsessed by the thought of Hitler’s two faces, and that for so long a time I did not see the second behind the first.  It was only toward the end, during the last months, that I suddenly became aware of the duality; and, significantly, my insight was connected with an aesthetic observation: I suddenly discovered how ugly, how repellent and ill proportioned, Hitler’s face was. How could I have overlooked that for so many years?”  Clearly, such thoughts stayed with him because on 8 December 1953 he noted: “Last night I had the following dream: In a rather sizable group, sometime toward the end of the war, I declare that everything is lost, that there is no longer a chance and the secret weapons do not exist.  The others in the dream remain anonymous. Suddenly Hitler emerges from their midst I am afraid that he will have heard my remark and may order my arrest.  My anxiety increases because Hitler’s retinue displays extreme iciness.  Nobody says a word to me.  Suddenly the scene changes.  We are in a house on a slope, with a narrow driveway.  Only gradually do I realize that it is Eva Braun’s [Eva Hitler (née Braun; 1912–1945)] house.  Hider comes to tea, sits facing me, but remains frosty and forbidding.  He chews the comers of his fingernails, as he so often did.  There are bloody places where they are bitten down to the quick.  Looking into his swollen face, I realize for the first time that perhaps Hitler wore his moustache in order to divert attention from his excessively large, ill-proportioned nose.  Now I am afraid that I will be arrested any moment because I have perceived the secret of his nose.  Heart pounding, I wake up.”

An eighteenth century carving of Janus in the style of a herm.

A part of the etymological legacy of the Roman Empire, the name Janus appears in several European languages.  In Danish (from the Latin Iānus), it’s a Latinization of the Danish given name Jens.  In Faroese, it’s a male given name which begat (1) Janussson or Janusarson (son of Janus) and (2) Janusdóttir or Janusardóttir (daughter of Janus).  In Estonian it’s a male given name.  In Polish, it’s both a masculine & feminine surname (the feminine surname being indeclinable (a word that is not grammatically inflected).  There is no anglicized form of the Latin name Janus.  Although it was never common and is now regarded by most genealogy authorities as "rare", when used in the English-speaking world the spelling remain "Janus".  Often, when Latin names were adopted in English, even when the spelling was unaltered, there were modifications to suit local phonetics but Janus is pronounced still just as it would have been by a Roman.

Tristar pictures used the Janus motif in promotional material for I Know Who Killed Me (2007).  Not well-received upon release, it's since picked up a cult following.

Dating from the 1580s, was from the Latin ianitor (doorkeeper, porter), from ianua (door, entrance, gate), the construct being ianus (arched passageway, arcade" + tor (the agent suffix).  The meaning “usher in a school” and later “doorkeeper” emerged in the 1620s white the more specific (and in Scotland and North America enduring) sense of “a caretaker of a building, man employed to attend to cleaning and tidiness” seems first to have been documented in 1708 (the now unused feminine forms were janitress (1806) & janitrix (1818).  Why janitor survived in general use in Scotland and North America and not elsewhere in the English-speaking world is a mystery although the influence of US popular culture (film and television) did see something of a late twentieth century revival and in  sub-cultures like 4chan and other places which grew out of the more anarchic bulletin boards of the 1980s & 1990s, a janitor is the (often disparaging) term for a content moderator for a discussion forum.

Augustus Orders the Closing of the Doors of the Temple of Janus (circa 1681), oil on canvas by Louis de Boullogne (1654–1733), Rhode Island School of Design Museum.

Among the more annoying things encountered by those learning English are surely Janus words, those with opposite meanings within themselves.  Examples include:  Hew can mean cutting something down or adhering closely to it.  Sanction may mean “formal approval or permission” or “an official ban, penalty, or deterrent”.  Scan can mean “to look slowly and carefully” or “quickly to glance; a cursory examination”.  Inflammable, which many take to mean “easy to burn” but the treachery of the word lies in the in- prefix which is often used as a negative, with the result that inflammable can be deconstructed as “not flammable”.  Trip can (and usually does) suggest clumsiness but can also imply some nimbleness or lightness of foot, as in the saying “trip the light fantastic”.  Oversight is a particularly egregious example.  To exercise oversight over someone or something is provide careful, watchful supervision yet an oversight is an omission or mistake.  In the ever-shifting newspeak of popular culture, the creation of the janus-word is often deliberate.  Filth can mean “of the finest quality”, wicked can mean “very good” and in the way which might have pleased George Orwell (1903-1950) "bad" has become classic “newspeak” (coined by Orwell for Nineteen Eighty-Four (1949) and used now to describe ambiguous, misleading, or euphemistic words, used deliberately to deceive, typically by politicians, bureaucrats or corporations).  “Bad weed” can mean the drug was either of fine or poor quality depending on the sentence structure: “that was bad weed” might well suggest it was of not good while “man, that was some bad weed” probably means it was good indeed.  Saying nice now seems rarely to mean what dictionaries say nice has come to mean but can variously describe something wonderful, appalling or disgusting.

Otrovert

Otrovert (pronounced ott-roh-vert)

A person unable to feel a connection to social groups or collectives; despite being welcomed and included in social settings, they feel like outsiders.

2025: A coining by US psychiatrist Dr Rami Kaminski (b 1954), who first used the word in his book his book The Gift of Not Belonging (2025), the construct being the Spanish otro (other; another) + -vert.  Otro was from the Latin alter, altera & alterum (the other), ultimately from the primitive Indo-European hélteros (the other of two); it may be compared with the Portuguese outro (from the Old Galician-Portuguese outro, from the Latin alterum (the other)) and the French autre (from Old French autre (another), from the Latin alterum).  The –vert suffix was from the Latin vertere (to turn) and was used to refer to a person with a particular personality which manifests when in the presence of others.

Otrovert is a noun; the noun plural is otroverts.  Because otrovert is a “hot word” (newly coined or an adaptation of an existing word and one which has in a short time become popular), most lexicographers are tagging it as “provisional”, the majority of “hot words and phrases” (think “six-seven”) fading from use and never gaining critical mass.  Even the idea of “popular: had (in this context) shifted because whereas once it could take months or years for a word or phrase to spread into general use, on the various platform on the internet, proliferation can be close to instant.  However, the tools used to assess “use” are rather brute-force and often are counting appearances in “lists” rather than “general use”.  For those reasons, in the technical sense, derived forms really don’t (yet) exist but if constructed the list (based on the model of other “-verts”) might include the nouns otrovertist, otroverting & otrovertness, the verb & adjective otroverted, adjectives otrovertish & otrovertesque & otrovertive and the adverbs otrovertedly & otrovertly.

Google ngram (a quantitative and not qualitative measure): Because of the way Google harvests data for their ngrams, they’re not literally a tracking of the use of a word in society but can be usefully indicative of certain trends, (although one is never quite sure which trend(s)), especially over decades.  As a record of actual aggregate use, ngrams are not wholly reliable because: (1) the sub-set of texts Google uses is slanted towards the scientific & academic and (2) the technical limitations imposed by the use of OCR (optical character recognition) when handling older texts of sometime dubious legibility (a process AI should improve).  Where numbers bounce around, this may reflect either: (1) peaks and troughs in use for some reason or (2) some quirk in the data harvested.

An ambivert is a person neither clearly extroverted nor introverted, but has characteristics of each, the construct being ambi- +‎ -vert.  Ambi- was from the Latin ambo (both) and was a doublet of the New Latin amphi-, from the Ancient Greek ἀμφί (amphí) (on both sides).  The dexter element in the Medieval Latin meant “right” and ambidexter thus was understood as “both hands being like a right hand”.  In English, the ambi- prefix is most familiar in “ambidextrous” (possessing an equal or functionally comparable ability to handle objects with both hands (in writing, music, sport etc) although it has from time to time been used figuratively (not taking sides in conflicts or being equally adept in more than one medium, genre, style etc) and even as a humorous synonym for “bisexual”.  When used in psychology, historically, ambiversion described someone with characteristics of both extroversion and introversion and thus suggested a “balanced personality”, the subject choosing to manifest the different characteristics according to what the circumstances seemed to demand.  Ambivert thus does not imply some sort of split personality or the existence of a condition like bi-polar disorder (the old manic depression) but simply reflects an individual able to undertake their social interactions in an appropriate manner.

Because the “vert words” are not really part of academic or clinical physiology, the definitions can be “elastic” and while centovert (being in the middle between introvert and extrovert) may be a synonym of ambivert, it may also be nuanced in that it suggests someone unable (or at least unwilling) to engage in introverted or extroverted behaviour, regardless of the circumstances.  A variant of the ambivert is the omnivert (someone fits into both extremes of the extroversion-introversion personality spectrum), the construct being omni + -vert.  Omni- ultimately was from the Latin omnis (all).  Again, because the “verts” are pop-psychology words there’s little to be gained from attempting to “parse the overlaps” (ie where one ends and another begins) and seems likely omniversion is simply an “enabling pre-condition” for one to possess if one is to attain the desirable “balanced state” of ambiversion.  Nobody seems yet to have coined ultravert, hypervert or ubervert but one need not spend long on social media to see the why such labels might be handy.

A self-described introvert: Lindsay Lohan explains she's an introvert; 2019 interview by broadcaster Howard Stern (b 1954).

Like other “-verts” of this ilk, otrovert was built on the model of the familiar introvert & extravert, the construct being intro + -vert.  An introvert (pronounced in-truh-vurt) is an individual who prefers (sometimes actively seeks) tranquil environments, limits social engagement and tends to a greater than average preference for solitude.  In anatomy & zoology there’s a technical meaning “a part (typically a hollow, cylindrical structure) that is or can be introverted, or turned in on itself (ie invaginate)) but the most commonly used is the psychological sense: a person characterized by concern primarily with their own thoughts and feelings.  Introverts are noted often for having a disposition that finds social engagement at least tiresome (and sometimes threatening), thus the preference for quiet solitude.  Introvert seem first to have appeared in print in the 1660s and was from the New Latin intrōvertere, the construct being intrō (within) + vertere (to turn).  The prefix intro- was from the Latin intro- (inwards) & intrā (within) + -ō (used as a verbalizer).  Although it’s not infrequent for introvert to be used as a synonym for “shy” (and in terms of observed behaviour the two phenomena can appear indistinguishable), they are definitionallly distinct.  While shyness is associated with timidity and social anxiety, introverts have a lack of interest in interpersonal engagement and a limited endurance for social contact; what that means is while the behaviours can often be the same, the underlying motivations differ.

Slaughterhouse-Five (1969) by Kurt Vonnegut.

Introvert & extrovert are popular terms of self-description but they can also be aspirational and while the classic stereotype is of the introvert who “wishes they were more outgoing” there are other types.  The US pediatrician Dr Mark Vonnegut (b 1947) wrote short stories and in one he described his father’s (the author Kurt Vonnegut (1922-2007)) desire to be a cynical, grumpy old man who despaired of humanity but could never quite manage it because of his “inherent optimism”.  As Dr Vonnegut put it, he was “…like an extrovert who wanted to be an introvert, a very social guy who wanted to be a loner, a lucky person who would have preferred to be unlucky. An optimist posing as a pessimist, hoping people will take heed.”  Explaining the difference, he added: “Introverts almost never cause me trouble and are usually much better at what they do than extroverts.  Extroverts are too busy slapping one another on the back, team building, and making fun of introverts to get much done.  Extroverts are amazed and baffled by how much some introverts get done and assume that they, the extroverts, are somehow responsible.”  On the basis of his clinical experience, he observed: “I understand perfectly why some of my autistic patients scream and flap their arms--it's to frighten off extroverts.”

An extrovert (pronounced ek-struh-vurt) is described typically as an outgoing, gregarious person who thrives in dynamic environments and seeks to maximize social engagement; in the jargon of psychology, it refers to someone characterized by extroversion; a person concerned primarily with the physical and social environment, thus the usual presentation as a person with a disposition energized through social engagement who tends to languish or chafe in solitude.  The word extrovert (the alternative spelling extravert (an example of the influence of German on psychology) is now rare) also emerged in the 1660s, the construct being extro- + vert.  In this case, extro- was a pseudo-Latinism prefix based upon the Latin extra- (outside, beyond), under the influence of the distinction between the Latin intro- (inwards) & intra- (inside; within).  In English, formations using the prefix tend to be restricted to words formed as antonyms of terms formed with intro-.

Introvert & extrovert (in their literal senses) were since the late seventeenth century used in science and medicine but both in the twentieth century entered general use when certain works by the Swiss psychiatrist, Carl Jung (1875–1961) were translated from German into English.  What seems to have given the words their greatest impetus was the appearance of commentaries on Jung written for a general audience and for these purposes binary concepts like “introvert” and “extrovert” were useful devices to encapsulate layers of meaning although the trigger may have been the 1918 paper Psycho-Analytic Study of August Comte [1798-1857; a seminal figure in sociology] by psychologist Dr Phyllis Blanchard (1895-1986).  Being a woman, Dr Blanchard has been neglected by history but, like the Austrian psychiatrist Sigmund Freud (1856-1939), Jung became what would now be called a “celebrity” psychoanalyst and that happened because advances in their field (and neurology) had made the public fascinated with the human mind and its processes (especially dreams).  Reflecting what may possibly be a professional distaste at their jargon ending up in pop-psychology texts, technical papers often use the spelling “extravert”, following Jung and his contemporaries.

The Gift of Not Belonging (2025) by Dr Rami Kaminski (b 1954).  Psychiatrist Dr Kaminski is the founder and director of the Institute for Integrative Psychiatry in New York City.

Dr Kaminski describes The Gift of Not Belonging as “…the first book to explore the distinct personality style of the otrovert - someone who lacks the communal impulse and does not fit in with any social group, regardless of its members - and to reveal all the advantages of being an otrovert and how otroverts contribute to the world.”  He explained that while otroverts enjoy deep and fulfilling one-on-one relationships, within groups they feel alienated, uncomfortable, and alone.  Unlike introverts, who crave solitude and are easily drained by social interactions, otroverts can be quite gregarious and rarely tire from one-on-one socialising; unlike loners, or people who have been marginalised based on their identity, otroverts are socially embraced and often popular - yet are unable to conform with what the group collectively thinks or cares about.  Dr Kaminski positions all this as “the great gifts of being an otrovert” by which he means someone with no affinity for a particular group is not constrained by their sense of self-worth being conditioned on the group's approval.  A champion of the otrovert, Dr Kaminski suggests they “must not be harassed to take part, but allowed to revel in their glorious difference.”

Despite vying with “psychopath” for the title of “most popular” words from psychology, neither introvert and extrovert have ever been used as diagnostic terms in the American Psychiatric Association's (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM); that doesn’t mean they’re not used by clinicians, just that they’re not part of the formal jargon.  That might seem curious given their not infrequent appearances in the published history of personality psychology including Jung’s original typology (codified in their most refined form in the 1920s), the ubiquitous MBTI (Myers–Briggs Type Indicator) and the Big Five model, where Extraversion is one of the five major personality traits.  These frameworks are however psychological, not psychiatric.  The DSM does of course have an extensive section on personality disorders and many of the traits related to introversion & extraversion appear including in (1) Avoidant Personality Disorder (social inhibition—links superficially to introversion but is not the same thing) and Histrionic or Narcissistic Personality Disorders (social boldness—superficially “extraverted” traits).

However, what the DSM’s editors have in recent decades done is to avoid the use of potentially ambiguous labels and focus instead on behavioural criteria that may indicate impairment or pathology.  Especially since the 1970s, the DSM has acknowledged (even championed) the idea that many “things” once classified as deviant are really part of the “normal” human condition; reflecting that paradigm, introversion & extraversion came to be understood as “normal-range” personality traits, not indicators of disorder.  As a general principle, the DSM appears to restrict the use of terms to instances where they relate to clinically significant impairment (the emphasis on the effect on the patient rather than the mechanics of process).  This approach was institutionalized with the release of DSM-5 (2013) in which the model clearly had become one of trait-based personality assessment.

To make the point, there exists in DSM-5 & DSM-5-TR (2022) the “Alternative DSM-5 Model for Personality Disorders, Section III” which describes personality traits that (more or less) correspond to what popular culture calls extraversion and introversion.  The editors however avoid the two popular words and instead breaks personality into trait domains with pathological versions of ordinary traits.  What general readers think of a “introversion” now appears in the DSM as “Detachment” although this is not pathologized unless it manifests in maladaptive extremes (chronic or persistent withdrawal; avoidance of social interaction; intimacy avoidance; a reluctance to form close relationships; anhedonia (inability to experience pleasure); mistrust of others; restricted affectivity (limited emotional expression)).  So, introverts can to some degree be “happy” with their state and just prefer frequent solitude and what the DSM calls “detachment” is invoked only when the trait is causing significant impairment or distress.

In the popular imagination, “extraversion” is associated with sociability, talkativeness, outgoing behaviour, enthusiasm (ie someone who is the “life of the party”).  That’s also obviously a “spectrum condition” and the DSM has never listed a single domain which could be classed as “high extraversion” which is good because high sociability isn’t intrinsically pathological.  Rather, should extraversion becomes maladaptive or extreme, the DSM classifies it across several domains:

(1) Attention-seeking (a facet of Antagonism) which manifests especially in Histrionic Personality Disorder.  Symptoms include an excessive need for approval, dramatic or provocative behaviour and an Intense desire to be the centre of attention.

(2) Grandiosity (a facet of Antagonism) which is characteristic of Narcissistic Personality Disorder, the symptoms including social boldness (masking fragile self-esteem) and entitlement and arrogance (which, in many cases, doesn’t manifest)

(3) Impulsivity & Risk Taking (a facet of disinhibition).  This is outgoing, sensation-seeking behaviour in its pathological form and is associated with thrill-seeking, poor impulse control and a tendency to act without considering the consequences

(4) Low Detachment: This is acknowledged as the “adaptive end of Detachment” but the editors seem to list it only to “close the circle”; it’s there because logically it has to be but is certainly not treated as a disorder.

So the DSM intentionally avoids the introvert/extrovert dichotomy which is how starkly it’s understood in popular use.  This “either-or” approach obviously doesn’t map onto the way the DSM treats personality traits as spectrums with only the margins (ie the dysfunctional extremes) described.  What that does is acknowledge there is introversion & extraversion which part of the “normal” human condition and not pathological.  Additionally it’s acknowledged the behavior which in one subject may indicate “significant impairment or distress” might in another not be of concern.