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 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.

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.

Pope Francis (b 1936; pope since 2013) 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”.

Colors: Lindsay Lohan with nails unadorned and painted.

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.  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 again 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 race 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 Sports Car Championship, they were the last of the straight-8s.

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 fenders; it would not be until later the platform was widened.  To achieve this, the engineers narrowed the cylinder heads, compelling both an 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 through their anyway small ports to make a turn of almost 180^o on their way to the tailpipe.

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.  Still, "light" is 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 ultimate power but it did lend itself to prodigious low-end torque, something much appreciated by Buicks previous generation of buyers who has enjoyed 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 and Chrysler’s Hemis were well-suited.  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 horsepower number to be achieved but at the expense of smoothness and tales of Buick buyers returning to the dealer to fix the “rumpity-rump” idle 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 reverse the valve use, the supercharger blowing the fuel-air mix through the exhaust ports and the exhaust gases through the larger intake ports.  Thus the for a while Nailhead enjoyed a career 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 cubic inch displacement and horsepower, publicized their torque output, confusing some (though probably not Buick buyers who were a loyal crew).  The unique appearance of the old nail still retains some 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 was the United States Air Force (USAF) which was much interested in power for its aircraft but also had a special need for torque on the tarmac and that briefly meant another small 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 National Aeronautics & Space Administration (NASA) 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 1950s & 1960s, the SR-71 used the Pratt & Whitney J58 turbojet engine which used an innovative, secondary air-injection system to 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.

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

At the time, the SR-71 was the most exotic aircraft on the planet but during testing and early in its career, to fly, 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 aero-engines became too big to start by hand but no on-board electrical systems were available 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.  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 bases the planes rarely used.

Thermal

Thermal (pronounced thur-muhl)

(1) Of, relating to, or caused by heat or temperature (also thermic); of, relating to, or of the nature of thermae.

(2) As (both noun and adjective) thermal blanket or thermal underwear (as a noun, always referred to in the plural (thermals) even if describing a single item), items designed to aid in or promote the retention of body heat.

(3) In meteorology, a column of rising air caused by local unequal heating by the sun of the land surface, especially such a current when not producing a cloud; widely used in aviation and of especial importance in gliding, a borrowing of the techniques used by birds. The air usually rises until it is in equilibrium with the surrounding atmosphere.

(4) In stonemasonry, a rough finish created with a blowtorch.

1756: From the French thermal (buffon), from the New Latin thermalis, from the Ancient Greek θέρμη (thérmē) (heat; feverish heat), from the primitive Indo-European gwher (to heat, warm).  The construct was therm + -al (from the Latin adjectival suffix -ālis, or the French, Middle French & Old French -el, -al; used mostly but not exclusively with word of Latin origin).  The sense of "having to do with heat" is first recorded 1837; the noun meaning "rising current of relatively warm air" was first noted in 1933 in the context of aviation.  Geothermal first used in 1875; hydrothermal in 1855, exothermal in 1874; athermanous in 1839, hyperthermia in 1878, isotherm in 1850, endothermic in 1869 (1947 as applied in biology) and thermometer as early as the 1597 although the most familiar (pre-digital) version with mercury encased in glass, was invented by Fahrenheit in 1714.  Thermal is adjective in the singular and a noun in the singular or plural, thermally is the adverb.  The most common derivations are the adjectives hyperthermal and the adverb hyperthermally but in engineering and science there’s also therm, therma, thermacogenesis, thermae, aerothermal, thermometric, thermometrical & thermaesthesia.  Thermal is a noun, verb & adjective; the noun plural is thermals.

Thermal Reactive Nail Polish

Thermal reactive nail polishes change color depending on both body and ambient temperature.  Nail polish is especially suitable for thermal reactivity because the extremities of the body (fingertips, toes, ears & nose) vary in temperature much more than parts closer to the core.  Usefully, they work with even the thickest base and top-coats which affords additional protection for the thermal-reactive chemicals, the color-changing properties affected not at all if multiple coats are applied.

The process is entirely heat-dependent and thus constantly variable.  In this example the reaction produces purple in reaction to cold and aqua to warmth; because the temperature of the nail greatly can vary between base and tip, the ombré effect (colors blending from one hue to another) will fluctuate.  The chemical reaction does rely on the top coat being fully dry and, depending on manufacturer, this can take up to an hour.  The special properties don't last forever but, if correctly sealed, stored in a dark place and not exposed to extremes of heat and cold, the liquid will for months continue to be reactive.

Chemically, the thermal reactivity works because the polish is infused with a leuco (“white” in Ancient Greek) dye, the word a little misleading in this context because leuco dyes have two forms: one clear, the other colored. The reversible transition between the two colors may be caused by heat (thermochromism), light (photochromism) or pH (halochromism) and in other (often industrial) applications, it’s possible irreversibly to change colors, usually from a redox reaction.

For thermal nail polish, the dye comes packaged in tiny spheres called microcapsules, each only 1-10 microns in diameter but containing three chemicals: (1) leuco dye which changes color reversibly, the color depending on the dye which, when combined with a proton or hydrogen ion, becomes colorless.  (2) A weak acid which acts as a catalyst, donating the hydrogen ion.  (3) A solvent which induces a color change at a desired temperature.  When cool, the solvent solidifies, the hydrogen remaining stuck to the acid and thus not interacting with the colored dye.  When hot, the solvent melts, the weak acid dissociates, the hydrogen ion binds to the dye, and the dye is colorless.  The temperature-shift range is about 5ºF (3ºC).

Those not content with the commercially available color combinations easily can brew their own thermal reactive polish.  Leuco dyes are available in many colors and come as a powder, slurry, epoxy, or water-based ink but only the powder is suitable and the transition range should hover 88ºF (31ºC) because nails are cooler than body temperature.  The choice of polish color dictates the result.  A white polish will produce a pastel result, a pale color will switch between the original and the combination of the leuco and the color so a mix of pink polish and a blue leuco dye yields a color shift from pink to purple.

To mix, place 1-2 small ball bearings in empty nail polish bottle and fill with polish to about half-way.  Add leuco dye to achieve desired color (about ⅛ teaspoon) and, if ambient temperature is high, chill the bottle to see result.  When mixing, cap bottle and gently roll it; do not shake because this will cause cavitation, the formation of air bubbles which impede the blending.  If the polish is too thick, add a few drops of nail polish thinner or clear top-coat but never acetone or other nail polisher remover because these chemicals ruin the mix.  Glitter or holo may be added according to taste.

Lindsay Lohan on skis in fuchsia, Falling for Christmas (Netflix (2022)), her thermal base layer unknown.

When skiing or mountain climbing, thermal underwear is usually the ideal choice for what is called the “thermal base layer”, a combination which consists usually of a top and a pair of leggings.  Outer layers of ski clothing perform better when a thermal base layer is worn because the moisture from the body rapidly is wicked away in a capillary action, permitting the breathable fabrics of the outer garments more efficiently to dissipate the moisture more efficiently.  It’s often thought the only purpose of thermal underwear is to increase body temperature but it’s the symbiosis between the thermal base layer and the outer coverings which regulate body temperature, maintaining comfort in both colder and warmer conditions.  By volume, most thermal underwear is made from Polyester (a type of plastic called polypropylene), often augmented with Lycra and all these garments are produced in a very tight weave which delivers good thermal qualities and what the manufacturers call a high “breathability factor”.

Also used is fine wool which, being a natural fibre, is preferred by many and it does posses the virtues of offering both comfort and efficient thermal qualities.  The choice between the types of construction is less about specific differences in thermal performance than how one’s skin reacts and sometimes this is something which can be judged only after prolonged exposure in a variety of temperatures.  All types are available in both short and long (sleeves & legs) versions and because the material is so thin, the longer cuts intrude not at all upon the fit of gloves and boots and the choice is again one of personal preference although, in extreme conditions, the full-versions should always at least be packed.

Hobnail

Hobnail (pronouned hob-neyl)

(1) A large-headed nail for protecting the soles of heavy boots and shoes, thus, when used as a modifier: hobnail boots.

(2) A small allover pattern consisting of small tufts, as on fabrics, or of small studs, as on glass.

(3) A rustic (obsolete).

(4) In medicine, a Slang term used by clinicians to describe the appearance of the organ in those suffering cirrhosis of the liver.

(5) In medicine, cellular morphology pathognomonic for clear cell adenocarcinoma of the ovary.

1585-1595: The construct is hob + nail.  Hob is related to hub, but the ultimate origin of both words is so obscure few etymologists have attempt to disentangle.  Nail in the sense of that which grows from the ends of digits is pre 900 from the Middle English nail & nayl, from the Old English negel (tapering metal) & nægl (fingernail (handnægl)).  It was cognate with the Old Frisian neil, the Old Saxon & Old High German nagal, the Dutch nagel & German Nagel and the Old Norse nagl (fingernail), all from the unattested Germanic naglaz; akin as derivative to the Lithuanian nãgas & nagà (hoof), the Old Prussian nage (foot) and the Old Church Slavonic noga (leg, foot). Nail in the sense used in "hobnail" is from the Middle English naylen, from the Old English næġlan, again, words with long, tortured histories.  The original sense was of the “short, thick nail with a large head", the construction using the element hob probably as an identification with the "rounded peg or pin used as a mark or target in games", that form of unknown origin and dating from the 1580s.  Because they were used to make heavy boots and shoes, the word was used figuratively from the seventeenth century for a "rustic person or simpleton", John Milton (1608–1674) in Colasterion (1645) writing “…the word Politician is not us'd to his maw, and therupon he plays the most notorious hobbihors, jesting and frisking in the luxury of his non-sense with such poor fetches to cog a laughter from us, that no antic hobnaile at a Morris, but is more hansomly facetious”.

From fireplace to fashion

Lindsay Lohan wearing hobnailed fabric.

Dating from 1505–1515, hub was a variant of obsolete hub hob (in a fireplace) and related to the obsolete hubbe from the 1510s and an etymology unrelated to the thirteenth century use as an affectionate diminutive for Robert or Robin.  Hob as a word to describe the side (the flat projection or iron shelf at the side of a fire grate, where things are put to be kept warm) of a fireplace was common by 1670s and in some English-speaking countries is used still to refer to the top cooking surface on a cooker or stove (the cooktop typically comprising several (often four) cooking elements also known as “rings” or elements”).  Etymologists are divided on whether the use of hob to describe a "clown, prankster" is a equating of such people with the yokels to whom it had long been applied or, a shortening for hobgoblin (the phrase “to play (the) hob" is documented in 1834 as meaning “to make mischief").  In quoits, a hob is a rounded peg used as a target.  In machine tools, it’s a kind of cutting tool, used to cut the teeth of a gear and can be used to refer to the hub or a wheel.  In zoology, a hub is a male ferret.  The long established meanings (1) the thin, horny plate at the ends of fingers and toes on humans and some other animals and (2) a spike-shaped metal fastener used for joining wood or similar materials ran in parallel.  It also one referred to a round pedestal on which merchants conducted business and a (now archaic) English unit of (usually cloth) measure length equivalent to 1 twentieth of an ell or one sixteenth of a yard (2 ¼ inches (57.15mm)).  The sense "fingernail" seems to have been the original.

The best known use of "hobnail" is in footwear.  The hobnailed boot (left) has been used since antiquity, both by workmen and the military and for the same reasons: durability and traction.  In the army of Ancient Rome, they were called caligae and remained common in military formations until well into the twentieth century, supplanted only as techniques with rubber and synthetic materials improved.  Before the development of crampons, they were widely used in mountaineering.  In Scotland, they're known also as "tackety boots").  Hobnail glassware (right) is a mass-produced novelty item and not part of the glass-blower's technique; it has no traditions.

Neon

Neon (pronounced nee-on)

In chemistry, a rare, colorless, odorless gaseous element; an inert gas (the second in the noble group) occurring in trace amounts in the atmosphere.  It glows reddish orange when electricity passes through it, as in a tube in an electric neon light, hence the industrial use in illuminated signs & lights although it’s used also in refrigeration because of the helpfully low melting & boiling points.

(2) A neon lamp, tube or device, in the singular or collectively; made of or formed by a neon lamp or lamps.

(3) A sign or advertising display formed from (or emulating) neon lamps.

(4) Of, relating to, or characteristic of an urban area brightly lit during hours of darkness and often associated with popular forms of entertainment.

(5) As in the phrase “in neon”, or “in neon lights”, adding emphasis to something (sometimes used derisively).

(6) Any of a range of bright, lurid colors, used particularly in fashion (lipsticks, nail polish etc) and as hair color products.

(7) As neon tetra (Paracheirodon innesi), a freshwater fish of the characin family (family Characidae) of order Characiformes, native to the Amazon basin in South America.  Because of its vivid coloring and robustness, the neon tetra is one of the most popular tropical fish in home aquariums.

1898: From the Ancient Greek νέον (néon), neuter of νέος (néos) (new; young), from the earlier νέϝος (néwos), from the Proto-Hellenic newos, from the primitive Indo-European néwos.  From the same source, English (and other languages gained the prefix –neo which was often used to form clade or taxonomic names indicating more recent branching than a morphologically or otherwise similar group.  The prefix neo- was from the Ancient Greek prefix νεο- (neo-), from νέος (néos) (new, young).  In organic chemistry it (1) had the specific technical meaning “having a structure, similar to that of neopentane, in which each hydrogen atom of a methyl group has been replaced by an alkyl group” and (2) a newly-discovered or synthesized variant of an existing compound.  The synonyms (in the sense of something new) were ceno- & nov-, the less used antonym paleo-.  Many words have been prefixed with neo- and not exclusively to indicate something wholly novel but increasingly to describe a revival or new variation of something including (1) in architecture: neo-classical, neo-gothic etc, (2) in economics: neo-liberal, neo-Keynesian etc, (3) in politics: neo-Nazi, neo-conservative, neo-fascist etc and (4) in religion: neo-evangelicalism, neo-Hasidism etc.  In chemistry, the meaning is quite specific but in general use the synonyms include blazing, brilliant, glowing, lambent, luminous, radiant, shining, vivid, flashing, glitzy, glossy, razzle-dazzle, effulgent & gleaming.  Neon is a noun & adjective; the noun plural is neons.

Sohio “Neon Patrol” in action, Cleveland, Ohio, July 1938.  Technicians from the Neon Patrol would travel between the company’s retail outlets, servicing the neon signage and effecting repairs when required.  The truck is an International D-15 with a special body.  The D Series (1937-1939) was a range of light, medium & heavy-duty trucks, easily distinguished from the more rectilinear C Series (1934-1936) by the curvilinear lines and the two-piece V-shaped windshield.  The line was replaced by the K (1940-1946) & KB Series (1947-1950).

The Standard Oil Company (Ohio) was a US petroleum company which operated between 1870-1987 and Sohio was one of a number of separate entities created in 1911 after the Standard Oil corporate trust (1882-1911) was broken up.  Standard Oil and British Petroleum (BP) in the 1960s entered into an intriguing (and tax-friendly) arrangement whereby BP gradually would increase its stake in Standard Oil, culminating eventually in acquisition.  Sohio as a corporate identity ceased operations in 1987 but BP continued to sell gas (petrol) under the brand until 1991, the name formally retired when the branding on the last Sohio gas station was replaced with BP signage.

Neon

Symbol: Ne.
Atomic number: 10.
Atomic weight: 20.1797.
Valency: 0.
Density: 0.899 90 kg/m³ / 0.9002 gm/liter at 0°C & 760 mm pressure.
Melting point: –248.59°C.
Boiling point: –246.08°C.

Neon nail-polish in 5-pack by Casey's Toys (part-number 52123) @ Aus$9.99.

Although in the United States it’s possible for citizens (in some cases children) lawfully to possess military-grade firearms and some truly impressive ordinance, in other fields the government is punctilious in providing people protection.  In 2012, Douglas Schoon (b 1954), Creative Nail Design (CND)’s chief scientific advisor, explained that in the US, the manufacture of neon nail-polish was unlawful, although, in what seemed a quirk of the law, the products remain lawful to wear.  However, that apparent anomaly isn’t actually strange or unique to neon nail-polish and reflects a regulatory environment where the need is to certify the safety of both the components and the processes used in the manufacturing process.  There are no concerns about the safety of the finished product, the skin and nails anyway a most effective barrier and the nature and volume of fumes breathed in by consumers “doing their nails” would substantively be identical to that of other nail-polishes.

Coffin-shaped nails in neon-green.  These are actually "press-on nails".

Neon polishes are prohibited simply because the colorants have never been officially registered with the US Food & Drug Administration (FDA).  Mr Schoon explained that “…what determines whether a color is neon is the chemical composition, just as it is with blues and greens”, adding that that any manufacturer could submit neon shades to the FDA, but it’s a costly and time-consuming process which is why many of the lurid shades available in the US, technically, are not neons.  Registration is only the first step in securing FDA approval and few small-scale manufacturers have the resources to go through a process from which others would gain equal benefit.  Imported neon polishes appear on many shelves but it’s not known if unlawful, small-scale manufacturing is being undertaken somewhere in the US.

Lindsay Lohan (b 1986, left) in neon outfits and singer-songwriter Billie Eilish (b 2001, right) with neon highlights.  Ms Eilish also went blonde, the result thought most pleasing.

As an adjective used of colors, neon refers to the quality of brightness rather than the red-orange colour which is the particular property of neon gas under electrical stimulation.  Thus, a “neon color” (or simply “neon”) is anything bright, lurid and used in clothing, accessories & enhancements (lipsticks, nail polish etc) or hair color products.

"Neon" advertising displays, Piccadilly Square, London, 1967.

Neon was discovered in 1898 by British chemists Sir William Ramsay (1852–1916) and Morris Travers (1872–1961) while working in their London laboratory during a series of experiments which also uncovered krypton & xenon, the other two residual rare inert elements remaining in dry air after nitrogen, oxygen, argon and carbon dioxide are removed.  In normal conditions a colorless, odorless & inert monatomic gas, it has about two-thirds the density of air and is noted for its emission in the spectrum of bright red when exposed to electrical current.  Although one of the known universe’s most common elements (fifth behind hydrogen, helium, oxygen and carbon), it’s rare on Earth, existing only in trace amounts in the atmosphere, attributable to it being highly volatile and thus never forming compounds which assume any solidity.

It needs thus to be extracted from air by an industrial process so is relatively expensive, its industrial uses limited to some specialized applications in refrigeration (by virtue of its low melting & boiling points) and the famous “neon lights” most associated with advertising and signage, the first of which was released in 1913, the term “neon sign” dating from 1927.  The distinctive bright red (tending to orange) light distinguished the first neon signs (created with curved neon-tubes) and in the narrow technical sense these are the only true “neon-lights” because tubes which generate other colors are made using either other noble gases or are instances of fluorescent lighting.  In hidden use, neon is also a component of various electrical devices including vacuum & wave tubes, current indicators and lightning arresters.

Tokyo after dark: less pink, more blue.

For decades, pink was the dominant color in the night-time Tokyo streetscape but in the twenty-first century observers began noting a shift to something darker.  The change is attributed not to the nation’s post 1989 slump in economic growth (the so-called “lost decade” of the 1990s apparently never having ended) but the development in 1993 by Japanese-American engineer Shuji Nakamura (b 1954) of a high-efficiency blue LED (light emitting diode) using gallium nitride (GaN) as the semiconductor material.  While green and red LEDs had for decades been in use, blue had proved elusive because the industry lacked a material suitable (and sufficiently cheap) to use at scale.  Nakamura san’s work built on earlier research by Japanese physicists Isamu Akasaki (1929–2021) and Japanese physicist Hiroshi Amano (b 1960) and what the three did was make possible both blue and white LEDs, the latter enabled by combining the blue with phosphors.  In 2014, the three were awarded the Nobel Prize in Physics.

1970 Plymouth Hemi 'Cuda in Limelight (left) and 2023 Dodge Challenger SRT Hellcat Redeye Jailbreak in Sublime (right). 

Lurid neon hues began to fade from the roads after being banished from the automotive color charts in the mid 1970s and while it can be debated if that was an aesthetic loss, it certainly made the option lists less linguistically interesting.  Like other manufacturers, Chrysler had some history in the coining of fanciful names for colors dating from the psychedelic era of the late 1960s when the choices included Plum Crazy, In-Violet, Tor Red, Limelight, Sub Lime, Sassy Grass, Panther Pink, Moulin Rouge, Top Banana, Lemon Twist & Citron Yella.  Although it may be an industry myth, the story told is that Plum Crazy & In-Violet (lurid shades of purple) were late additions because the killjoy board refused to sign-off on Statutory Grape.  Plymouth called their lime green Limelight while Dodge used Sub Lime.  That the colors vanished during the 1970s was not because of changing tastes but in response to environmental & public health legislation which banned the use of lead in automotive paints; without the additive, production of the bright colours was prohibitively expensive.  Advances in chemistry meant that by the twenty-first century brightness could be achieved without the addition of lead so Dodge revived psychedelia for a new generation although Sub Lime became Sublime.  There was still a price to be paid however, Sublime, Red Octane, Sinamon Stick and Go Mango all costing an additional US$395 while the less vivid shades listed at US$95.  The resurrected "neon look" proved popular although only within the high-performance niche, most of the market preferring more "dignified" tones such as black, white, silver and many variations of gray although there's still the odd malcontent who orders blue or red.

2015 Dodge Challenger SRT in Sublime (code FB).  Literalists should note this is NOT what Greta Thunberg (b 2003) meant when she spoke of "green vehicles".

There was of course once a time when the term “green vehicle” had a simple, unambiguous meaning but were a driver to contest a parking ticket, the outcome might depend on how a court would apply the “Vagliano rule”, established by the House of Lords in Bank of England v Vagliano Bros (1891) AC 107.  The Vagliano rule is a principle of statutory interpretation and holds that when interpreting a statute, courts should start by considering the natural meaning of the words in the statute itself, without referring to previous case law or historical background, unless the language is ambiguous.  The rule is of such significance because it prioritizes the literal and ordinary meaning of words over any interpretation which could be derived if other factors are allowed to intrude.

In his judgment, Lord Herschell (Farrer Herschell, 1837–1899; Lord High Chancellor of Great Britain 1886 & 1892-1895) wrote: “I think the proper course is, in the first instance, to examine the language of the statute and to ask what is its natural meaning, uninfluenced by any considerations derived from the previous state of the law, and not to start with inquiring how the law previously stood, and then, having ascertained that, to see whether the statute will bear an interpretation which is in accordance with it. If the statute is clear, its provisions must prevail, whatever the previous law may have been. If the statute is ambiguous, then, and only then, may the history of the law be referred to.”  Whether in the 2020s a judge would be persuaded “Green Vehicle” should for this purpose be read-down to permit gas-guzzling V8s (simply on the basis of being painted a certain color), to occupy parking spots allocated exclusively to the machines of which Ms Thunberg would approve may be doubtful but any driver will always be able to find a lawyer willing to run the case.