Online Etymology Dictionary

smear (n.): "mark or stain left by smearing," 1610s, from smear (v.). Sense of "small quantity prepared for microscopic examination" is from 1903. Meaning "a quantity of cream cheese, etc., smeared on a bagel" is by 1999, from Yiddish shmir. The earliest noun sense in English is "fat, grease, ointment" (c. 1200), from Old English had smeoru "fat, grease," cognate with Middle Dutch smere, Dutch smeer, German Schmer "grease, fat" (Yiddish schmir), Danish smør, Swedish smör "butter."
smear-case (n.): 1829, semi-translation of German Schmier-käse; see smear (v.) + cheese (n.).
smee (n.): "pintail duck," 1660s, reduced from earlier smeath (1620s), probably from Middle Dutch smeente.
smegma (n.): sebaceous secretion, 1819, from Latin, from Greek smegma "a detergent, soap, unguent," from smekhein "to wipe off, wipe clean, cleanse," from PIE root *sme- "to smear" (source also of Czech smetana "cream," and see smear (v.)). So called from resemblance; a medical coinage, the word seems not to have been used in its literal Greek sense in English before this. Related: Smegmatic.
smell (v.): late 12c., "emit or perceive an odor," not found in Old English, perhaps cognate with Middle Dutch smolen, Low German smelen "to smolder" (see smolder). However, OED says "no doubt of Old English origin, but not recorded, and not represented in any of the cognate languages." Related: Smelled or smelt; smelling.

Smelling salts (1840), used to revive the woozy, typically were a scented preparation of carbonate of ammonia. Smell-feast (n.) "one who finds and frequents good tables, one who scents out where free food is to be had" is from 1510s ("very common" c. 1540-1700, OED). Smell-smock "licentious man" was in use c. 1550-c. 1900. To smell a rat "be suspicious" is from 1540s.
smell (n.): "odor, aroma, stench," late 12c.; "faculty of perceiving by the nose," c. 1200; see smell (v.). Ousted Old English stenc (see stench) in most senses.
smelly (adj.): 1854, from smell (n.) + -y (2). Related: Smelliness.
smelt (v.): mid-15c. (implied in smelter), from Dutch or Low German smelten, from Proto-Germanic *smelt- (source also of Old High German smelzan, German schmelzen "to melt"), from PIE *smeld-, variant of *mel- "soft." Thus the word is from a variant of the stem of Old English meltan "to melt" (see melt (v.)). Related: Smelted; smelting.
smelt (n.): Old English smelt "sardine, small salmon-like sea fish," cognate with Dutch smelt "sand eel," Danish smelt (c. 1600). OED notes that it has a peculiar odor (but doesn't suggest a connection with smell); Klein suggests a connection with the way the fish melts in one's mouth. Century Dictionary speculates it means "smooth" and compares Old English smeolt, smylt "serene, smooth."
smelter (n.): mid-15c., agent noun from smelt (v.).
SMERSH (n.): Soviet Army counter-espionage organization begun during World War II, 1953, from Russian abbreviation of smert' shpionam "death to spies." Introduced in English by "James Bond" author Ian Fleming.
smicker (adj.): "elegant, fine, gay," from Old English smicere "neat, elegant, beautiful, fair, tasteful." Hence smicker (v.) "look amorously" (1660s); smickering "an amorous inclination" (1690s).
smidge (n.): short form of smidgen, 1902, American English dialect.
smidgen (n.): 1845, perhaps from Scottish smitch "very small amount; small insignificant person" (1822). Compare Northumbrian dialectal smiddum "small particle of lead ore" (1821).
smilax: type of lilaceous plant, c. 1600, from Latin, from Greek smilax "blindweed," also used of the yew and a kind of evergreen oak.
smile (v.): c. 1300, perhaps from Middle Low German *smilen or a Scandinavian source (such as Danish smile "smile," Swedish smila "smile, smirk, simper, fawn"), from Proto-Germanic *smil-, extended form of PIE root *smei- "to laugh, smile" (source also of Old English smerian "to laugh at, scorn," Old High German smieron "to smile," Latin mirus "wonderful," mirari "to wonder"). Related: Smiled; smiling.

Gradually pushed the usual Old English word, smearcian (modern smirk), into a specific, unpleasant sense. Of the eyes, from 1759. Figuratively, as indicating favor or encouragement, from c. 1400. Romance, Celtic, and Slavic languages tend to use a diminutive of the word for "laugh" to mean "smile" (such as Latin ridere "laugh;" subridere "smile"), perhaps literally "small laugh" or "low laugh."
smile (n.): 1560s, from smile (v.).
smiley (adj.): also smily, "inclined to smile," 1848, from smile (n.) + -y (2). Smiley-face (n.) is from 1981; as a computer icon from 1987.
smirch (v.): late 15c., "to discolor, to make dirty," of uncertain origin, perhaps from Old French esmorcher "to torture," perhaps also "befoul, stain," from es- "out" (see ex-) + morcher "to bite," from Latin morsus, past participle of mordere "to bite" (see mordant). Sense perhaps influenced by smear. Sense of "dishonor, disgrace, discredit" first attested 1820.
smirch (n.): 1680s, "a soiling mark or smear," from smirch (v.). Figurative use by 1862.
smirk (v.): Old English smearcian "to smile." No exact cognates in other languages, but probably related to smerian "to laugh at, scorn," from Proto-Germanic *smer-, *smar-, variant of PIE *smei- "to smile;" see smile (v.), which after c. 1500 gradually restricted smirk to the unpleasant sense "smile affectedly; grin in a malicious or smug way." In some 18c. glossaries smirk is still simply "to smile." Related: Smirked; smirking. The noun is recorded by 1560s.
smirk (n.): 1550s, from smirk (v.).
Smirnoff (n.): proprietary name of a brand of vodka, said to have been in use since 1914.
smite (v.): "to hit, strike, beat," mid-12c., from Old English smitan, which however is attested only as "to daub, smear on; soil, pollute, blemish, defile" (strong verb, past tense smat, past participle smiten), from Proto-Germanic *smitan (source also of Swedish smita, Danish smide "to smear, fling," Old Frisian smita, Middle Low German and Middle Dutch smiten "to cast, fling," Dutch smijten "to throw," Old High German smizan "to rub, strike," German schmeißen "to cast, fling," Gothic bismeitan "to spread, smear"). "The development of the various senses is not quite clear, but that of throwing is perh. the original one" [OED]. Watkins suggests "the semantic channel may have been slapping mud on walls in wattle and daub construction" and connects it with PIE *sme- "to smear;" Klein's sources also say this.

Sense of "slay in combat" (c. 1300) is from Biblical expression smite to death, first attested c. 1200. Meaning "visit disastrously" is mid-12c., also Biblical. Meaning "strike with passion or emotion" is from c. 1300.
smith (n.): Old English smið "blacksmith, armorer, one who works in metal" (jewelers as well as blacksmiths), more broadly, "handicraftsman, practitioner of skilled manual arts" (also including carpenters), from Proto-Germanic *smithaz "skilled worker" (source also of Old Saxon smith, Old Norse smiðr, Danish smed, Old Frisian smith, Old High German smid, German Schmied, Gothic -smiþa, in aiza-smiþa "coppersmith"), from PIE root *smi- "to cut, work with a sharp instrument" (source also of Greek smile "knife, chisel"). Attested as a surname since at least c.975.
smith (v.): Old English smiðian "to forge, fabricate, design," from the source of smith (n.). Related: Smithed; smithing.
Smith & Wesson: proprietary name of a type of firearm, 1860, from the gunsmith firm of Horace Smith (1808-1893) and Daniel B. Wesson (1825-1906) in Springfield, Massachusetts.
smithereens (n.): "small fragments," 1810, smiddereens, from Irish smidirin, diminutive of smiodar "fragment," perhaps with diminutive ending as in Colleen.
Smithfield: place in London, celebrated since at least 17c. as a market for cattle and horses, later the central meat market. In various colloquial expressions. Originally Smethefield, from Old English smethe "smooth" (see smooth (adj.)). Smithfield ham (1908, American English) is from a town of that name in Virginia.
Smithsonian: "Smithsonian Institute," named for English scientist and philanthropist James Smithson (1765-1829), who left a legacy to the U.S. government to found it. The mineral smithsonite also is named for him.
smithy (n.): "workshop of a smith," c. 1300, from Old Norse smiðja (cognate with Old English smiððe), from Proto-Germanic *smith-ja-, from PIE smi- (see smith (n.)).
smitten (adj.): mid-13c., "struck hard, afflicted, visited with disaster," past participle adjective from smite. Sense of "inspired with love" is from 1660s.
smock (n.): Old English smoc "garment worn by women, corresponding to the shirt on men," from Proto-Germanic *smukkaz (source also of Old Norse smokkr "a smock," but this is perhaps from Old English; Old High German smoccho "smock," a rare word; North Frisian smok "woman's shift," but this, too, perhaps from English).

Klein's sources, Barnhart and the OED see this as connected to a group of Germanic sm- words having to do with creeping or pressing close, such as Old Norse smjuga "to creep (through an opening), to put on (a garment)," smuga "narrow cleft to creep through; small hole;" Old Swedish smog "a round hole for the head;" Old English smugan, smeogan "to creep," smygel "a burrow." Compare also German schmiegen "to cling to, press close, nestle;" and Schmuck "jewelry, adornments," from schmucken "to adorn," literally "to dress up."

Watkins, however, traces it to a possible Germanic base *(s)muk- "wetness," figuratively "slipperiness," from PIE root*meug- "slimy, slippery" (see mucus). Either way, the original notion, then, seems generally to have been "garment one creeps or slips into," by the same pattern that produced sleeve and slip (n.2).

Now replaced by euphemistic shift (n.2); smock was the common word down to 18c., and was emblematic of womanhood generally, as in verb smock "to render (a man) effeminate or womanish" (1610s); smocker "man who consorts with women" (18c.); smock-face "person having a pale, effeminate face" (c. 1600). A smock-race (1707) was an old country pastime, a foot-race for women and girls with a smock as a prize. Modern meaning "woman's or child's loose dress or blouse" is from 1907; sense of "loose garment worn by artists over other clothes" is from 1938.
smog (n.): 1905, blend of smoke and fog, formed "after Lewis Carrol's example" [Klein; see portmanteau]. Reputedly coined in reference to London, and first attested there in a paper read by Dr. H.A. des Voeux, treasurer of the Coal Smoke Abatement Society, though he seems not to have claimed credit for coining it.
At a recent health congress in London, a member used a new term to indicate a frequent London condition, the black fog, which is not unknown in other large cities and which has been the cause of a great deal of bad language in the past. The word thus coined is a contraction of smoke fog "smog" -- and its introduction was received with applause as being eminently expressive and appropriate. It is not exactly a pretty word, but it fits very well the thing it represents, and it has only to become known to be popular. ["Journal of the American Medical Association," Aug. 26, 1905]
Smaze (with haze (n.)) is from 1953.
smoggy (adj.): 1905, from smog (n.) + -y (2). Related: Smogginess.
smokable (adj.): 1839, from smoke (v.) + -able. Related: Smokably; smokability.
smoke (n.1): late Old English smoca (rare) "fumes and volatile material given off by burning substances," related to smeocan "give off smoke," from Proto-Germanic *smuk- (source also of Middle Dutch smooc, Dutch smook, Middle High German smouch, German Schmauch), from PIE root *smeug- "to smoke; smoke" (source also of Armenian mux "smoke," Greek smykhein "to burn with smoldering flame," Old Irish much, Welsh mwg "smoke").
There is no fyre without some smoke [Heywood, 1562]
The more usual noun was Old English smec, which became dialectal smeech. Abusive meaning "black person" attested from 1913, American English. Smoke-eater "firefighter" is c. 1930. Figurative phrase go up in smoke "be destroyed" (as if by fire) is from 1933. Smoke-alarm first attested 1936; smoke-detector from 1957.
smoke (v.): Old English smocian "to produce smoke, emit smoke," especially as a result of burning, from smoke (n.1). Meaning "to drive out or away or into the open by means of smoke" is attested from 1590s. Meaning "to apply smoke to, to cure (bacon, fish, etc.) by exposure to smoke" is first attested 1590s. In connection with tobacco, "draw fumes from burning into the mouth," first recorded 1604 in James I's "Counterblast to Tobacco." Related: Smoked; smoking. Smoking gun in figurative sense of "incontestable evidence" is from 1974.
smoke (n.2): "cigarette," slang, 1882, from smoke (n.1). Also "opium" (1884). Meaning "a spell of smoking tobacco" is recorded from 1835.
smoke-screen (n.): 1915, as a form of military camouflage, from smoke (n.1) + screen (n.); 1926 in the figurative sense. The association of smoke with "deception, deliberate obscurity" dates back to at least 1560s.
smokeless (adj.): "emitting little smoke," 1580s, from smoke (n.1) + -less.
smoker (n.): 1590s, "one who cures meat," agent noun from smoke (v.). Meaning "one who smokes tobacco" is from 1610s. Railway meaning "smoking car" is from 1875. Smoker's cough attested from 1898.
smokestack (n.): also smoke-stack, 1833, from smoke (n.1) + stack (n.).
smokey (adj.): variant of smoky. As a noun, sometimes short for Smokey Bear.
Smokey Bear (n.): "state policeman," 1974, from truckers' slang, in reference to the wide-brim style of hat worn by state troopers (the hats so called by 1969). Ultimately the reference is to a popular illustrated character of that name, dressed in forest ranger gear (including a hat like those later worn by state troopers). He was introduced in 1944 by the U.S. Forest Service and the Wartime Advertising Council in a campaign to lower the number of forest fires in the West.
smoky (adj.): early 14c., "emitting smoke," from smoke (n.) + -y (2). Meaning "filled with smoke" and meaning "resembling smoke" are from late 14c. Of flavors, from 1540s; of colors, from 1550s. Related: Smokiness.
smolder (v.): c. 1300 (implied in smoldering), "to smother, suffocate," related to Middle Dutch smolen, Low German smelen, Flemish smoel "hot," from Proto-Germanic *smel-, *smul-. The intransitive meaning "burn and smoke without flame" is first recorded 1520s, fell from use 17c. (though smoldering persisted in poetry) and was revived 19c. Figurative sense "exist in a suppressed state; burn inwardly" is from 1810. Related: Smouldered; smolderingly. Middle English also had a noun smolder meaning "smoky vapor, a stifling smoke."
smooch (v.): 1932, alteration of dialectal verb smouch "to kiss" (1570s), possibly imitative of the sound of kissing (compare German dialectal schmutzen "to kiss"). An earlier alteration produced smudge (v.) "to kiss, caress" (1844). Related: Smooched; smooching. As a noun by 1942.
smoochy (adj.): "amorous, meant for kissing," 1947, from smooch (n.) + -y (2).
smooth (adj.): Old English smoð "smooth, serene, calm," variant of smeðe "free from roughness, not harsh, polished; soft; suave; agreeable," of unknown origin and with no known cognates. Of words, looks, "pleasant, polite, sincere" late 14c., but later "flattering, insinuating" (mid-15c.). Slang meaning "superior, classy, clever" is attested from 1893. Sense of "stylish" is from 1922.

Smooth-bore in reference to guns is from 1812. smooth talk (v.) is recorded from 1950. A 1599 dictionary has smoothboots "a flatterer, a faire spoken man, a cunning tongued fellow." The usual Old English form was smeðe, and there is a dialectal smeeth found in places names, such as Smithfield, Smedley.