stupidity (n.) Look up stupidity at Dictionary.com
1540s, "want of intelligence," from Latin stupiditatem (nominative stupiditas) "dullness, stupidity, senselessness," from stupidus "confounded, amazed; dull, foolish" (see stupid). It also at various times meant "lack of feeling or emotion" (1560s); "stupor, numbness" (c.1600).
stupor (n.) Look up stupor at Dictionary.com
late 14c., from Latin stupor "insensibility, numbness, dullness," from stupere "be stunned" (see stupid).
stuporous (adj.) Look up stuporous at Dictionary.com
1843, from stupor + -ous. Related: Stuporously; stuporousness.
sturdy (adj.) Look up sturdy at Dictionary.com
c.1300, "hard to manage, reckless, violent," from Old French estordi (11c., Modern French étourdi) "violent," originally "dazed," past participle of estordiir "to daze, stun, stupefy," from Vulgar Latin *exturdire, which some presume to be from Latin intensive prefix ex- + turdus "thrush." Barnhart suggests the notion is of thrushes eating grape remnants at wineries and behaving as if drunk (Italian tordo "thrush" also means "simpleton," and French has the expression soûl comme une grive "drunk as a thrush"). OED, however, regards all this as "open to grave objection." Century Dictionary compares Latin torpidus "dull."

Sense of "solidly built, strong and hardy" first recorded late 14c. Related: Sturdily; sturdiness. Sturdy-boots "obstinate person" is from 1762; a sturdy beggar in old language was one capable of work (c.1400).
sturgeon (n.) Look up sturgeon at Dictionary.com
c.1300, from Anglo-French sturgeon, Old French esturjon, from Frankish *sturjo- or another Germanic source, from Proto-Germanic *sturjon- (cognates: Old High German sturio "sturgeon," Old English styria). Cognate with Lithuanian ersketras, Russian osetr "sturgeon;" the whole group is of obscure origin, perhaps from a lost pre-Indo-European tongue of northern Europe, or from the root of stir (v.). Medieval Latin sturio, Italian storione, Spanish esturion are Germanic loan-words.
Sturm und Drang (n.) Look up Sturm und Drang at Dictionary.com
1844, literally "storm and stress," late 18c. German romanticism period, taken from the title of a 1776 romantic drama by Friedrich Maximilian von Klinger (1752-1831), who gave it this name at the suggestion of Christoph Kauffmann. See storm (n.) + throng (n.).
Sturmabteilung (n.) Look up Sturmabteilung at Dictionary.com
1923, from German, literally "storm detachment;" paramilitary force of the Nazi Party, founded 1921, repressed 1934, also know by its initials, S.A.; also see Brown Shirt.
stutter (v.) Look up stutter at Dictionary.com
1560s, frequentative form of stutt "to stutter," from Middle English stutten "to stutter, stammer" (late 14c.), cognate with Middle Low German stoten "to knock, strike against, collide," from Proto-Germanic *staut- "push, thrust" (cognates: Old English stotan, Old High German stozan, Gothic stautan "to push, thrust"), from PIE *(s)teu- (1) "to hit, beat, knock against" (see steep (adj.)). The noun is attested from 1854. Related: Stuttered; stuttering; stutterer.
sty (n.1) Look up sty at Dictionary.com
"pen for pigs," Old English sti, stig "hall, pen" (as in sti-fearh "sty-pig"), from Proto-Germanic *stijan (cognates: Old Norse stia "sty, kennel," Danish sti, Swedish stia "pen for swine, sheep, goats, etc.," Old High German stiga "pen for small cattle"). Meaning "filthy hovel" is from 1590s.
sty (n.2) Look up sty at Dictionary.com
"inflamed swelling in the eyelid," 1610s, probably a back-formation from Middle English styany (as though sty on eye), mid-15c., from Old English stigend "sty," literally "riser," from present participle of stigan "go up, rise," from Proto-Germanic *stigan, from PIE root *steigh- "to stride, step, rise" (see stair).
sty (v.) Look up sty at Dictionary.com
"go up, ascend" (obsolete), Old English stigan (past tense stah, past participle stigun, common Germanic (Old Norse, Old Frisian stiga, Middle Dutch stighen, Old Saxon, Old High German stigan, German steigen, Gothic steigan), from PIE root *steigh- "go, rise, stride, step, walk" (see stair).
Stygian (adj.) Look up Stygian at Dictionary.com
"pertaining to Styx or the nether world," 1560s, from Latin Stygius, from Greek Stygios, from Styx (genitive Stygos); see Styx.
style (n.) Look up style at Dictionary.com
early 14c., stile, "writing instrument, pen, stylus; piece of written discourse, a narrative, treatise;" also "characteristic rhetorical mode of an author, manner or mode of expression," and "way of life, manner, behavior, conduct," from Old French stile, estile "style, fashion, manner; a stake, pale," from Latin stilus "stake, instrument for writing, manner of writing, mode of expression," perhaps from the same source as stick (v.)). Spelling modified incorrectly by influence of Greek stylos "pillar," which probably is not directly related. As distinguished from substance, 1570s. Meaning "mode of dress" is from 1814.
style (v.) Look up style at Dictionary.com
c.1500, "address with a title;" 1560s, "to give a name to," from style (n.). Meaning "to arrange in (fashionable) style" (especially of hair) is attested from 1934. Slang sense of "act or play in a showy way" is by 1974, U.S. Black slang. Related: Styled; styling.
stylet (n.) Look up stylet at Dictionary.com
1690s in surgical and scientific senses, from French stylet, from Italian, from Latin stylus (see style (n.)).
stylish (adj.) Look up stylish at Dictionary.com
"conformable to approved fashion or taste," 1795, from style (n.) + -ish. Good is understood. Related: Stylishly; stylishness.
stylist (n.) Look up stylist at Dictionary.com
1795 of writers distinguished for excellence or individuality of style; 1937 of hairdressers, from style (n.) + -ist.
stylistic (adj.) Look up stylistic at Dictionary.com
"of or relating to style," 1843; see style (n.) + -istic.
stylite (n.) Look up stylite at Dictionary.com
ascetic living on the top of a pillar, 1630s, from Ecclesiastical Greek stylites, from stylos "pillar" (see stet).
stylize (v.) Look up stylize at Dictionary.com
1894 (implied in stylized), from style (n.) + -ize. Perhaps a translation of German stilisieren.
stylus (n.) Look up stylus at Dictionary.com
1728, "stem-like part of a flower pistil," alteration of Latin stilus "stake, stylus;" spelling influenced by Greek stylos "pillar" (see stet). Meaning "instrument for writing" is from 1807.
stymie (v.) Look up stymie at Dictionary.com
1857, in golf, from stymie (n.) "condition in which an opponent's ball blocks the hole" (1834), perhaps from Scottish stymie "person who sees poorly," from stime "the least bit" (early 14c.), of uncertain origin. General sense of "block, hinder, thwart" is from 1902. Related: Stymied.
styptic (adj.) Look up styptic at Dictionary.com
c.1400, from Old French stiptique or directly from Latin stypticus "astringent," from Greek styptikos, from styphein "to constrict, draw together." As a noun, c.1400, from Late Latin stypticum. Related: Styptical.
styrene (n.) Look up styrene at Dictionary.com
colorless hydrocarbon, 1885, from Styrax, name of a genus of trees (the chemical is found in their resin), 1786, from Latin styrax, from Greek styrax, the tree name, of Semitic origin (compare Hebrew tsori "terebinth resin"). Form influenced by Greek styrax "shaft of a lance."
Styrofoam (n.) Look up Styrofoam at Dictionary.com
1950, trademark name (Dow Chemical Co.), from -styr- (from polystyrene) + connective -o- + foam (n.).
Styx Look up Styx at Dictionary.com
late 14c., the Greek river of the Underworld, literally "the Hateful," cognate with Greek stygos "hatred," stygnos "gloomy," from stygein "to hate, abominate," from PIE *stug-, extended form of root *steu- (1) "to push, stick, knock, beat." Oaths sworn by it were supremely binding and even the gods feared to break them. The adjective is Stygian.
suasion (n.) Look up suasion at Dictionary.com
late 14c., from Old French suasion (14c.) and directly from Latin suasionem (nominative suasio) "a recommending, advocacy, support," noun of action from past participle stem of suadere "to urge, incite, promote, advise, persuade," literally "recommend as good" (related to suavis "sweet"), from PIE *swad- "sweet, pleasant" (see sweet (adj.)). Survives chiefly in phrase moral suasion (1640s). Latin Suada was the goddess of persuasion.
suasive (adj.) Look up suasive at Dictionary.com
c.1600, from Middle French suasif, or else formed in English from Latin suasus (see suasion) + -ive. Related: Suasively; suasiveness.
suave (adj.) Look up suave at Dictionary.com
early 15c., "gracious, kindly, pleasant, delightful," from Latin suavis "agreeable, sweet, pleasant (to the senses), delightful," from PIE root *swad- "sweet, pleasant" (see sweet (adj.)). In reference to persons, sense of "smoothly agreeable" first recorded 1815 (implied in suavity). Related: Suavely.
suavity (n.) Look up suavity at Dictionary.com
c.1400, "pleasantness, delightfulness; kindness, gentleness," from Latin suavitatem (nominative suavitas) "sweetness, agreeableness," from suavis (see suave). Some later senses are from French suavité, from Old French soavite "gentleness, sweetness, softness," from the Latin word.
sub (n.) Look up sub at Dictionary.com
shortened form of substitute (n.), 1830; the verb in this sense is from 1853. Related: Subbed; subbing. From 1917 as short for submarine (n.).
sub judice Look up sub judice at Dictionary.com
Latin, literally "under a judge," from ablative singular of iudex "judge," from iudicare (see judge (v.)). "Under judicial consideration," hence not yet decided.
sub rosa Look up sub rosa at Dictionary.com
"privately, secretly," Latin, literally "under the rose," which was regarded as a symbol of secrecy.
sub voce Look up sub voce at Dictionary.com
Latin, literally "under the word or heading." A common dictionary reference, usually abbreviated s.v.
sub- Look up sub- at Dictionary.com
word-forming element meaning "under, beneath; behind; from under; resulting from further division," from Latin preposition sub "under, below, beneath, at the foot of," also "close to, up to, towards;" of time, "within, during;" figuratively "subject to, in the power of;" also "a little, somewhat" (as in sub-horridus "somewhat rough").

This is said to be from PIE *(s)up- (perhaps representing *ex-upo-), a variant form of the root *upo- "from below," hence "turning upward, upward, up, up from under, over, beyond" (cognates: Sanskrit upa "near, under, up to, on," Greek hypo "under," Gothic iup, Old Norse, Old English upp "up, upward," Hittite up-zi "rises"). The Latin word also was used as a prefix and in various combinations.

In Latin assimilated to following -c-, -f-, -g-, -p-, and often -r- and -m-. In Old French the prefix appears in the full Latin form only "in learned adoptions of old Latin compounds" [OED], and in popular use it was represented by sous-, sou-; as in French souvenir from Latin subvenire, souscrire (Old French souzescrire) from subscribere, etc.

The original meaning is now obscured in many words from Latin (suggest, suspect, subject, etc.). The prefix is active in Modern English, sometimes meaning "subordinate" (as in subcontractor); "inferior" (17c., as in subhuman); "smaller" (18c.); "a part or division of" (c.1800, as in subcontinent).
sub-acute (adj.) Look up sub-acute at Dictionary.com
also subacute, 1752, from sub- + acute.
sub-aqueous (adj.) Look up sub-aqueous at Dictionary.com
also subaqueous, 1670s, from sub- + aqueous.
sub-arctic (adj.) Look up sub-arctic at Dictionary.com
1834, from sub- + arctic.
sub-atomic (adj.) Look up sub-atomic at Dictionary.com
also subatomic, 1874, from sub-atom (1868, from sub- + atom) + -ic.
sub-category (n.) Look up sub-category at Dictionary.com
also subcategory, 1855, from sub- + category (n.).
sub-deb (n.) Look up sub-deb at Dictionary.com
"girl who will soon 'come out;'" hence, "girl in her mid-teens," 1917, from sub- + deb.
sub-giant (n.) Look up sub-giant at Dictionary.com
also subgiant, in astronomy, of stars, 1937, from sub- + giant (n.).
sub-machine gun (n.) Look up sub-machine gun at Dictionary.com
"light, portable machine gun," 1926, from sub- + machine gun.
sub-Saharan (adj.) Look up sub-Saharan at Dictionary.com
1955, from sub- + Saharan (see Sahara).
subaltern (n.) Look up subaltern at Dictionary.com
"junior military officer," 1680s, earlier more generally, "person of inferior rank" (c.1600), noun use of adjective subaltern "having an inferior position, subordinate" (1580s), from Middle French subalterne, from Late Latin subalternus, from Latin sub "under" (see sub-) + alternus "every other (one), one after the other" (see alternate (adj.)).
subclass (n.) Look up subclass at Dictionary.com
also sub-class, 1802, from sub- + class (n.).
subcommittee (n.) Look up subcommittee at Dictionary.com
also sub-committee, c.1600, from sub- + committee.
subconscious (adj.) Look up subconscious at Dictionary.com
1823, "not wholly conscious, feebly conscious" (implied in subconsciously), from sub- + conscious. First attested in De Quincey. The noun, in the psychological sense ("mental processes taking place without consciousness"), is attested from 1886, from adjectival sense "occurring in the mind, but not in consciousness;" earlier noun was subconsciousness (1845).
subcontinent (n.) Look up subcontinent at Dictionary.com
also sub-continent, 1845, from sub- + continent (n.). Related: Subcontinental.
subcontract (n.) Look up subcontract at Dictionary.com
also sub-contract, "contract for carrying out all or part of a previous contract," 1817, from sub- + contract (n.). As a verb from 1828 (in Shakespeare it means "be betrothed again"). Related: Subcontracted; subcontracting.