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.

Nipple

Nipple (pronounced nip-uhl)

(1) In anatomy, the small, conical projection near the center of the areola of each mammary gland (breast); also called mamilla, papilla or teat.  In females, the nipple contains the outlets of the milk ducts.

(2) Something resembling (often in scaled-up form) a female’s nipple, as the mouthpiece of a nursing bottle or pacifier (in some places an informal word for a pacifier).

(3) Any device resembling a nipple in shape or function.

(4) A mechanical device through which liquids or gases can be passed in a regulated manner; as grease nipple a small drilled bush, usually screwed into a bearing (or other component needing periodic replenishment of a greasing agent) through which grease is introduced.

(5) In plumbing & gas-fitting, a short piece of pipe with threads on each end, used for joining valves.

(6) Any small physical protrusion on an automotive, a machine part or any other part that fits into a groove on another part (now rare).

(7) In computer (hardware) slang, the pointing device in the centre of the keyboard of certain laptops, partially fulfilling the functionality of a mouse, trackball or track-pad (although some (male) users insist it is called “the clit”).

(8) In pre-modern ballistics, a perforated segment that fits into part of the breech of a muzzle-loading gun, on which the percussion cap is fixed.

(9) In the design of bicycles, an internally threaded piece which holds a bicycle spoke in place on the rim.

(10) To fit (a baby's bottle etc) with a nipple (archaic).

(11) To give one's nipple to (a baby) to allow breastfeeding (archaic).

1520–1530: From the Middle English nipple, from the earlier neble, nibble, nible & nepil (all of which may be derived from nib & neb (tip; point).  The Old English nypel (elephant’s trunk) was formed analogously as “a protuberance from one's neb”.  The late twelfth century pap & pappe (nipple of a woman's breast) was first attested in Northern and Midlands writing, probably from a Scandinavian source (there’s no record in the Old Norse but there was the dialectal Swedish pappe), from the primitive Indo-European imitative root pap- (to swell), the source also of the Latin papilla (nipple) which may have influenced the English papula (a swelling, pimple) and the Lithuanian papas (nipple).  The spellings neple, nypil, nyppell, neapel, neaple, neble and all obsolete.  Nipple is a noun & verb, nippling is a verb and nippleless & nippled are adjectives; the noun plural is nipples.

One extinct verb which, perhaps surprisingly, wasn’t revived even after it became apparent trends of use on the internet suggested it might be helpful, was expapillate (bare the breasts to the nipples), identified by the outstandingly good Online Etymology Dictionary as an entry in an early English "dictionary", published in eleven editions between 1623 and the 1650s.  The book was neither a prescriptive or descriptive work encompassing the whole language but was described as “An Interpreter of Hard English Words”, an approach others later took including Wilfred Funk (1883–1965) in his Word Origins and Their Romantic Stories (1950), the idea being to focus on the less known or more obscure.  The construct of expapillate was ex- + papillate.  The ex- prefix was from the Middle English, from words borrowed from the Middle French, from the Latin ex (out of, from), from the primitive Indo-European eǵ- & eǵs- (out).  It was cognate with the Ancient Greek ἐξ (ex) (out of, from), the Transalpine Gaulish ex- (out), the Old Irish ess- (out), the Old Church Slavonic изъ (izŭ) (out) & the Russian из (iz) (from, out of).  The “x” in “ex-“, sometimes is elided before certain constants, reduced to e- (eg ejaculate).  The Latin papillate was the vocative masculine singular of papillātus (having nipples or buds; shaped like a nipple or bud) and was used in English as a transitive verb (to cover with papillae) and intransitive verb (to take the form of a papilla, or of papillae).

In 1974, The British Medical Journal (BMJ) used the term "guitar nipple" to describe "the irritation to the breast that can occur from the pressure of the guitar against the body."  That was indicative of the trend in the English-speaking world for newly-identified (and sometimes novel) conditions to be constructed with English elements, rather than the Latin historically used.  In the same spirit, two years later a contributor to the JAMA (Journal of the American Medical Association) was more imaginative still, coining "hot pants syndrome" when documenting cases in which a burn to the skin had been induced by a patient carrying a battery-powered transistor radio in the pocket of their trousers.  There was also in 1978 the New England Journal of Medicine's (NEJM) "disco digit" which referred to "a sore or infected finger caused by too much finger snapping while dancing."    

Jaguar tool kit supplied with 1966 E-Type (XKE, 1961-1974).  The grease gun (left) was used to force grease into various components through grease nipples.  This was a regular part of automobile maintenance until recent decades and is still a feature of the servicing schedules of heavy vehicles and machinery.

Until the 1970s, it was common for cars to need periodic “greasing” of certain components, a process which involved attaching a “grease gun” to a “grease nipple” which permanently was mounted on the relevant part; manually, the gun (usually a type of plunger) was used to force grease through the nipple.  This was undertaken either by owners, chauffeurs or mechanics at service stations who routinely would perform an “oil and grease” which included (all or some of): changing the engine, gearbox & differential oil, replacing the filter(s) and greasing all required grease points.  On more expensive vehicles, “one-shot lubrication” systems (known also as CLS (centralized lubrication systems) & ALS (automated lubrication systems)) were introduced during the 1920s, the technology adapted from the hardware used in aviation.  Although some attempts were made to create wholly automated systems, the most widely used were those which incorporated a foot pump for the driver to press at specified intervals; this action forced grease from a central reservoir to the required points.  Being a sealed system, this meant that nowhere in the system were grease nipples required (although some often still were included in components which demanded less frequent attention or were of a design which made their inclusion in the CLS plumbing too difficult.  ALS systems remain common in many places including heavy machinery, ships and the industrial plant used in factories, power plants etc.

The standard grease nipple used on the Jaguar E-Type (XKE) (left) and a diagram with a legend listing the E-Type's oil, brake fluid, transmission fluid and grease nipple locations.  The grease nipples are indicated by the obelus (†).  In automobiles, by the 1970s the need for multiple grease points or one-shot lubrication had begun to be eliminated (although some older designs maintained the legacy for decades) as advances in metallurgy and lubrication technology permitted the development of sealed, maintenance-free components which are “packed with grease" and thus “lubricated for life”.  However, for heavy-duty machines such as trucks and earth-moving equipment operating in adverse conditions, there are often still components demanding regular greasing and thus grease nipples are still a thing.

Also a thing is the “nipple orgasm”, at least for those for whom a nipple is a “hardwired erogenous zone” responsive to stimulation; that's a sub-set of the population and there are probably no reliable estimates of the prevalence.  Although in humans orgasms are typically thought an ejaculative, vaginal or clitoral phenomenon, sexologists list more than a dozen types, varying in instance or intensity based on the individual, the circumstances and sensitivity to stimulation.  When warming to the topic, these specialists will also discuss the details of “energetic orgasms” (which can, without physical touch, be triggered by meditation or fantasy) and “sleep orgasms”, said to have been experienced by an “estimated” 37% of women and 83% of men.  Quite how those numbers were obtained isn’t clear but helpfully, in 2011, New Jersey-based neuroscientist, psychotherapist & sex therapist Dr Nan Wise (b 1967) undertook a study to reveal how nipple stimulation affects the brain.  What Dr Wise wanted to build on was the existing understanding “…the clitoris, vagina and cervix are mapped on the genital sensory cortex”, something which sits between the brain’s two hemispheres and which she labels “hedonistic pleasure zone” or, more illustratively “the crotch of the brain”.

What Dr Wise did was have the study’s subjects stimulated with various mental fantasies while in an MRI (magnetic resonance imaging) machine, allowing her team to observe how distinct parts of the brain responded to various experiences.  The results were generally in line with expectations except that nipple stimulation proved an outlier.  While her hypothesis had been there would have been activity in the brain region associated with chest sensation (the theory being nipple orgasms might occur because stimulation of the organ releases oxytocin, a hormone that can cause uterine contractions, potentially leading to vaginal orgasm), instead it was found nipple stimulation activated the genital sensory cortex itself, leading Dr Wise to conclude: “The nipples are a hardwired erogenous zone, like the genitals, when nipples are stimulated, the brain gets activated, and regions processing the sensation communicate with those responsible for pleasure.”  This tied in with one of the accepted dictums in neuroscience: “neurons that fire together wire together” and the study’s findings do seem to suggest it is plausible there exists a neural pathway between the nipples and the genitals.  Sexologists however caution individual responses will vary and techniques which produce pleasing results for one will induce no response in others.  So, YMMV (your mileage many vary) and the sexologists recommend experimentation.

The SKIMS Nipple Bra

Wearing it well: Kim Kardashian in SKIMS "nipple bra"

The admirable (and much admired) Kim Kardashian (b 1980) in October 2023 announced the latest addition to her SKIMS product line: a bra with “built in” nipples, designed to be prominent enough obviously to protrude through clothing.  Said to offer the “ultimate shock factor” (although after the shocks of the last decade-odd, some of which those associated with Kardashian clan have instigated, that may be hyperbolic) the viewer response suggested many weren’t certain whether product was real or a gimmick designed to attract publicity.  It certainly attracted publicity but turned out to be real (with SKIMS part number).  Even if the concept wasn't as “innovative” as claimed, the promotional approach in the video certainly was, the spin being that if women can don a bra to emulate one of the more pleasing consequences of cold weather, the psychological effect might be they’ll be less inclined to turn on (or up) the air-conditioner, thus reducing energy use, thereby lowering carbon emissions, meaning a lesser contribution to the concentration of atmospheric CO₂ (and other greenhouse gasses) which causes accelerated climate change including higher temperatures.  That seems to be drawing a long bow but doubtlessly somewhere there will be published research which can be spun to support (or at least not disprove) each of the steps in the internal Kardashian logic.  It was certainly an example of the way commerce is attempting to monetize concerns about climate change.  

As Ms Kardashian put it: “The earth’s temperature is getting hotter and hotter. Sea levels are rising. The ice sheets are shrinking. I’m no scientist, but I believe everyone can do their skillset to do their part.  That’s why I’m introducing a brand-new bra with a built-in nipple so matter how hot it is, you’ll always look cold.  Some days are hard but these nipples are harder. And unlike the icebergs, these aren’t going anywhere.”  The bra was said to be available in six colors with a stated “10% of sales” (the exact math of that calculation not disclosed) to be a “one off donation” to 1% for the Planet (a multi-national collective of businesses pledged to gifting at least 1% of their annual revenue to “environmental causes”).  So it sounded like a real product with a real part-number (not then listed) but there were those who thought the release date being Halloween (October 31) might suggest it might not be wholly serious.  Even had it not been real, it would have been a good case-study for students of such things learning the craft of the promotional video clip, the only opportunity missed being Ms Kardashian should first have appeared in a scientist's white lab coat, peeling it off as she spoke the words "I'm no scientist".  The part-number's later appearance in the catalogue verified the availability.   

The 1970s: Rudi's sheer bra (left & right) and the original Nipple Bra.

It’s not a new idea.  In the early 1970s, several manufacturers advertised a line of bras with cups in a sheer fabric which offered coverage and support (within a limited mass range) but clung to the nipples' definition, the most celebrated being those of Austrian-born Rudolf "Rudi" Gernreich (1922–1985), remembered as the "designer" of the "monokini" (ie a bikini supplied without the top part).  This approach was for those who wanted to display the profile of their own nipples.  The "Nipple Bra" offered enhanced engineering was the ancestor of the SKIMS bra in that rather than using, as Herr Gernreich did, the human body's "built-in" nipples, it provided some.  The pitch all those decades ago was aimed at those who wanted to look “provocative” and in 1975 to achieve that the “Nipple Bra” cost US$20 (US$114.42 adjusted for 2023) so Ms Kardashian setting her price at US$120.00 seems not unreasonable.  The somewhat obtuse contribution to averting climate change aside, reaction to the product included the observation the bra will provide permanently “perfectly aligned nipples”, something not always achieved by the real things because, like most body parts, between left and right, there’s often some variation in size, shape, direction or distance from the ground.  Like many aspects of structural engineering, “perfect alignment” is achieved often with slight adjustments to variables like strap length.

Rudi not required: Lindsay Lohan displays perfect alignment, Venice Beach, Los Angeles, California, 2011.

In the United States, patent law exists to protect inventions, processes, and methods rather than abstract ideas and the general criteria (interpreted with some latitude) for eligibility is that an invention should be novel, non-obvious, and useful.  What does qualify is the implementation or embodiment of an idea in a tangible form so while a mere thought or concept can't be patented, a specific application or embodiment of that idea can be and this includes a new product, process, machine, or composition of matter.  Within all that, patents can be granted to cover improvements made to existing inventions.  Whether SKIMS have applied for or been granted a patent isn't clear but several for products in this vein have been granted over the last 50-odd years.  On 24 August 1976 Mr Jakob E. Schmidt of Charlestown, Indiana was granted U.S. patent #3976083 (Brassiere Having Simulated Nipples) as well as #4241737 & #4127128 covering “Brassiere Having Simulated Nipples and Attachable-Detachable Nipple Simulators”.

Conceptual drawing supplied with application for patent #3976083 (Brassiere Having Simulated Nipples), granted 24 August 1976.  The patent expired 24 August 1993.

The abstract filed with the application for #3976083 included: A brassiere is disclosed having cups which are provided with a nipple-like protuberance simulating the bulge of a natural nipple. The nipple-like bulge or protuberance may be a built-in component of the brassiere, usually situated under the fabric of the cup; a component which is permanently attached to the external surface of the brassiere cop; or an individual structure which may be attached to or detached from the brassiere cup as will, by means of several linkage and attachment mechanisms.  Simulated nipples for a brassiere would offer an acceptable compromise for ladies who do not wish to go without a brassiere and a welcome release from the subconscious effects of the suppression brought on by wearing brassieres of the types variously available, which obliterate the nipple.  That’s informative but Ms Kardashian might have phrased things in a more "Tik-Tok friendly" way. 

A nipple patch (left), the nipple patch writ large to function as a special-purpose bra (centre) and the advertising concept (right) which could be used by the manufacturers of either the "nipple bra" or the "nipple patch".  All that would be required is transposing the photographs, depending on whether the object was to display or conceal.

However, while one niche market will like the idea of being “so provocative”, there are others who find the sight of their own nipples “too provocative” and for this niche, there are ranges of products which offer coverage and concealment, smoothing away any suggestion of a nipple with patches which can be worn under bras with cups of even the most sheer fabric.  Self-adhesive (using a skin-friendly temporary glue), they can also be used without a bra and the same technology has been adapted to larger-scale units which actually function as a bra.  Marketed as being ideal to be used when wearing “backless” dresses or tops, they’re also said to be easier to use than the “fashion tape” (better known in the industry as “booby tape” or “tit tape”), especially if being self-applied.  Helpfully, if one changes one’s mind after having smoothed away the nipples, stick-on nipples are available in a range of styles and colors.

Piece from Miguel Castro Freitas’s “Stardust Aphrodite” collection for Mugler, Paris Fashion Week, October. 2025.

Miguel Castro Freitas’s (b 1980) first collection for Mugler was called “Stardust Aphrodite” and the designer described the pieces as “a trilogy of glorified clichés”, the three elements being (1) oversize and bulky, with big fluffy fabrics or shoulder pads, (2) severely tailored with extreme hourglass figures or (3) lightweight, sheer dresses; critics detected some overlap in the use of the motifs.  Although there were a number of nods to Mugler’s historic use of materials in bulk for dramatic effect, the collection otherwise tended to the “less”, one eye catching piece a gown with sparkly silver stars, its straps hung from bare-breasted nipple piercings.  To re-assure those whose toes had curled, critics noted that one was made from “a very lightweight fabric”.  The technique had be seen before, a “nipple grown” the best-remembered thing from the catwalk from one of Mugler’s shows in 1998 and this year’s model was an acknowledged homage but apart from that, it certainly was on-theme, Victoria’s Secret unlikely to see much business generated from those taken with Stardust Aphrodite.

A fragment from Fashion Feed’s take on Paris Fashion Week, 2025.

Of course the point of the catwalk is it makes it possible to see a garment in motion, interacting with the body.  That can be transformative: an outfit that on a hanger or mannequin seemed bland or lifeless can, when worn by a strutting model, come alive although equally, one which seemed admirable when static might reveal flaws of design or in construction once on the move.  Had the already infamous “nipple-piercing gown” been assessed purely on the technical criteria usually applied it would have been judged a success because the suspended sparkly chiffon flowed and swished as the designer knew it would but that achievement wasn’t much commented upon because the usual factions quickly were posting, the l'art pour l'art (art for art's sake) crowd calling the piece “an artistic vision” and dismissing criticism as the unwanted intrusion of a resurgent “purity culture” while those who disapproved called it “inappropriate” and yet another example of the way women’s bodies are exploited for the benefit of the “male gaze”.

One perhaps daring observation was that despite “many of the biggest names in women’s fashion being gay men… their designs often over-sexualise women instead of empowering them.”  Quite how much of the collective energy of gay men over the years been devoted to empowering women isn't known but Indian fashion commentator Pranjal Jain (b 2001) seemed to speak for her faction by adding that having a model parade “…a topless dress down the runway” and presenting it homage to the original of a quarter-century earlier was absurd because in the particular social & political context of the late 1990s such a dress could be understood as something “sensuous and provocative” but in 2025, “…what the fuck was the topless dress doing next to structured blazers and mini dresses?  I can tell you, the dress was a social media stunt engineered for virality.  Yet again, a man using a woman’s body for shock value.”  “Here”, she concluded, “is a perfect example of how fashion is political and historical, because context matters.”  As it has been for centuries, the critical deconstruction of frocks remains a serious matter.

Chappell Roan on the red carpet, Grammy Awards, Crypto.com Arena, Los Angeles, California, February 2026.  The rich auburn hair worked well with the hues of the gown and body art.

Even if Mugler’s “Stardust Aphrodite” didn’t at once migrate from the Paris catwalk to high street stores, the house didn’t abandon the motif and in February 2026, singer Chappell Roan (stage name of Kayleigh Rose Amstutz, b 1998) wore another of Mugler's interpretations (this time a burgundy gown) for the walk down the red carpet at the 68^th Annual Grammy Awards.  Predictably the event’s most publicized outfit, men everywhere doubtless were intrigued at the possibilities but the immediate reaction of women, regardless of their views of the aesthetic, may have been an involuntary curling of the toes as they imagined donning the gown.  That phenomenon is known as “mirror-touch synesthesia” which describes the experience when, upon observing another individual being touched or injured, a corresponding tactile or pain sensation is elicited in the anatomically matching location in the observer’s own body.  It’s very common but is a spectrum condition, most experiencing it as momentary sensation but in rare cases there have been patients for whom the effects have been long-lasting.  Technically, it’s triggered by a (usually temporary) reduction in the “self–other distinction” at the neural processing level, the causes thought to include (1) an heightened cross-activation between the visual and somatosensory cortices and (2) hyperactive or atypical functioning of the brain’s mirror neuron system.  There seems to be evidence an individual’s susceptibility to mirror-touch synesthesia is more significant in frequency of occurrence than the perception of the extent of the sensation (eg severity of an injury) witnessed.

Mirror-touch synesthesia is quite specific in its “virtual emulation” and differs from the vicarious responses (typically, a flinching when seeing someone suffer an injury) in being usually qualitatively stronger and manifested by a location-specific somatic sensation; it may run in parallel with emotional empathy (which happens typically without the literal bodily sensation) but is a separate phenomenon.  There are of course exceptions and the traditional (probably culturally obligatory) reaction of cricketers seeing a batsman struck “in the groin region” by a ball (delivered sometimes at 90 mph (145 km/h) or more) is one of mirth rather than empathy.

Drawing the lens: Chappell Roan photographed in front of the backdrop.

It would however seem the toes of mirror-touch synesthetes may uncurl because in the many photographs and video clips circulated, Ms Roan appeared not at all discomforted and the physics of that would have been determined by (1) the use of faux nipple piercings, (2) the lightweight fabric and (3) the gathering at the waist, ensuring each nipple had to bear the weight only of a few square inches of material.  No doubt pleased (if not surprised) by the interest generated, Ms Roan insisted it was not “that outrageous of an outfit”, adding “the look’s actually so awesome and weird” before concluding “I recommend just exercising your free will; it’s really fun and silly.”  The look was complimented with temporary body art, an extensive lace panel spread over her bare back with a pony on the chest, both credited to artist Jenny Collins of Puppy Puppy Playtime; the gold choker and earrings were by Buccellati.  Perhaps disappointing some, the outfit made only a one-off appearance on the red carpet, Ms Roan changing into something warmer when serving as an award-presenter.

Skims Ultimate Pierced Nipple Push-up Bra.

Of course, for such gowns to work (and that really is the correct expression), it relies on the wearer's nipples having appropriate fittings and these can be real (as body-piercings) or faux (attached with an adhesive or clamping device, the latter on the model of “clip-on” earrings).  However, what the use of light-weight fabrics should make possible is the material's attachment directly to the nipples with either a transparent surgical-grade glue or strategically placed double-sided tape ("boob-tape" or "tit-tape" in the jargon) but some of the effect would be lost because of the extent of the surface area of skin such adhesives would require.  More to the point, were it not done with genuine fittings (piercings or clamed-on), some of the “edginess” would be lost and it was this vibe Skims picked up on in the promotional video for “The Ultimate Pierced Nipple Push-up Bra”.  The tag line was: “Our sexiest bra gets even hotter with a faux nipple piercing design so you can get the ‘Ooo’ without the ouch!” and there’s no reason why, for certain events (if not the street), a Mugleresque gown couldn’t be hung from the bra’s fittings.  Done well, it could look good although Ms Jain likely would remain unimpressed.

Skims promotional video: “The Ultimate Pierced Nipple Push-up Bra”.