Online Etymology Dictionary

stylet (n.): 1690s in surgical and scientific senses, from French stylet, from Italian, from Latin stylus (see style (n.)).
stylish (adj.): "conformable to approved fashion or taste," 1795, from style (n.) + -ish. Good is understood. Related: Stylishly; stylishness.
stylist (n.): 1795 of writers distinguished for excellence or individuality of style; 1937 of hairdressers, from style (n.) + -ist.
stylistic (adj.): "of or relating to style," 1843; see style (n.) + -istic.
stylite (n.): ascetic living on the top of a pillar, 1630s, from Ecclesiastical Greek stylites, from stylos "pillar," from PIE root *stā- "to stand, set down, make or be firm" (see stet).
stylize (v.): 1894 (implied in stylized), from style (n.) + -ize. Perhaps a translation of German stilisieren.
stylus (n.): 1728, "stem-like part of a flower pistil," alteration of Latin stilus "stake, stylus;" spelling influenced by Greek stylos "pillar." Meaning "instrument for writing" is from 1807.
stymie (v.): 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.): 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.): 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.): 1950, trademark name (Dow Chemical Co.), from -styr- (from polystyrene) + connective -o- + foam (n.).
Styx: 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.): 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.): c. 1600, from Middle French suasif, or else formed in English from Latin suasus (see suasion) + -ive. Related: Suasively; suasiveness.
suave (adj.): 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.): 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.): 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: 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: "privately, secretly," Latin, literally "under the rose," which was regarded as a symbol of secrecy.
sub voce: Latin, literally "under the word or heading." A common dictionary reference, usually abbreviated s.v.
sub-: 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" (source also of 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.): also subacute, 1752, from sub- + acute.
sub-aqueous (adj.): also subaqueous, 1670s, from sub- + aqueous.
sub-arctic (adj.): 1834, from sub- + arctic.
sub-atomic (adj.): also subatomic, 1874, from sub-atom (1868, from sub- + atom) + -ic.
sub-category (n.): also subcategory, 1855, from sub- + category (n.).
sub-deb (n.): "girl who will soon 'come out;'" hence, "girl in her mid-teens," 1917, from sub- + deb.
sub-giant (n.): also subgiant, in astronomy, of stars, 1937, from sub- + giant (n.).
sub-machine gun (n.): "light, portable machine gun," 1926, from sub- + machine gun.
sub-Saharan (adj.): 1955, from sub- + Saharan (see Sahara).
subaltern (n.): "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.): also sub-class, 1802, from sub- + class (n.).
subcommittee (n.): also sub-committee, c. 1600, from sub- + committee.
subconscious (adj.): 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.): also sub-continent, 1845, from sub- + continent (n.). Related: Subcontinental.
subcontract (n.): 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.
subcontractor (n.): 1810, from sub- + contractor, or else an agent noun from subcontract.
subculture (n.): 1886, in reference to bacterial cultures, from sub- + culture (n.). From 1922 in reference to human cultures.
subcutaneous (adj.): also sub-cutaneous, "under the skin," 1650s, from sub- + cutaneous. Related: Subcutaneously.
subdenomination (n.): also sub-denomination, 1620s, from sub- + denomination.
subdivide (v.): early 15c. (transitive), from Late Latin subdividere from sub in the sense of "resulting from further division" (see sub-) + Latin dividere (see division). Intransitive sense is from 1590s.
subdivision (n.): early 15c., "process of dividing into smaller parts;" mid-15c., "portion of land that has been divided," noun of action from subdivide. Sense of "plot of land broken into lots for housing development" is from 1911.
subdominant (n.): also sub-dominant, 1793, in music, from sub- + dominant (n.).
subduce (v.): mid-15c., "to delete;" 1540s, "to withdraw oneself" (from a place, allegiance, etc.), from Latin subducere "to draw away, withdraw, remove," from sub- (see sub-) + ducere "to lead" (see duke (n.)). Related: Subduced; subducing.
subduct (v.): 1570s, "subtract," from Latin subductus, past participle of subducere "to draw away, take away" (see subduce). Geological sense is from 1971, a back-formation from subduction. Related: Subducted; subducting.
subduction (n.): early 15c., "withdrawal, removal" (originally of noxious substances from the body), from Latin subductionem (nominative subductio) "a withdrawal, drawing up, hauling ashore," noun of action from past participle stem of subducere "to draw away, take away" (see subduce). Geological sense is attested from 1970, from French (1951).
subdue (v.): late 14c., "to conquer and reduce to subjection," from Old French souduire, but this meant "deceive, seduce," from Latin subducere "draw away, lead away, carry off; withdraw" (see subduce). The primary sense in English seems to have been taken in Anglo-French from Latin subdere and attached to this word. Related: Subdued; subduing. As an associated noun, subdual is attested from 1670s (subduction having acquired other senses).
subdued (adj.): c. 1600, "subjugated," past participle adjective from subdue. Meaning "calmed down, reduced in intensity" is recorded from 1822.
subfusc (adj.): "moderately dark, brownish," 1710, from Latin subfuscus, variant of suffuscus, from sub- (see sub-) + fuscus "dark, dusky" (see obfuscate). Related: Subfuscous "dusky."
subgroup (n.): also sub-group, 1825, from sub- + group (n.).