A- (3) prefix meaning "not," from Gk a-, an- "not," from pie base *ne "not" (see un-)

solace (n.) --- comfort, consolation, c.1290, from O.Fr. solas, from L. solacium, from solatus, pp. of solari "to console, soothe," from PIE base *sel- "of good mood, to favor" (cf. Gk. hilaros "merry," O.E. gesælig "happy;" see silly). The verb is recorded from 1297.

solar --- c.1450, from L. solaris "of the sun," from sol "sun" (see sol). Meaning "living room on an upper story" is from O.E., from L. solarium (see solarium). Solar power is attested from 1915. Solar system is attested from c.1704. Solar plexus (1771) "complex of nerves in the pit of the stomach," apparently so called from its central position in the body.

solarium --- 1891, "part of a house exposed to the sun," earlier "sundial" (1842), from L. solarium "sundial," also "a flat housetop," lit. "that which is exposed to the sun," from sol "sun" (see sol).

solder --- c.1350, sawd, from O.Fr. soldure, from solder "to join with solder," from L. solidare "to make solid," from solidus "solid" (see solid). Modern form is from c.1420. The -l- is still pronounced in Great Britain. The noun is first attested 1374.

soldier (n.) --- c.1300, from O.Fr. soudier "one who serves in the army for pay," from M.L. soldarius "a soldier" (cf. It. soldato and Fr. soldat "soldier," which is borrowed from It.), lit. "one having pay," from L.L. soldum, from acc. of L. solidus, a Roman gold coin (see solidus). The verb meaning "to serve as a soldier" is first recorded 1647; to soldier on "persist doggedly" is attested from 1954.

sole (adj.) --- single, c.1386, from O.Fr. soul (fem. soule), from L. solus "alone," of unknown origin, perhaps related to se "oneself," from PIE reflexive base *swo- (see so). Adv. solely is attested from 1495.

sole (n.1) --- bottom of the foot, c.1325, from O.Fr. sole, from L. solea "sandal, bottom of a shoe," from solum "bottom, ground, soil," of unknown origin. The verb meaning "to provide with a sole" is recorded from 1570.

sole (n.2) --- flatfish, 1252, from O.Fr. sole, from L. solea "a kind of flatfish," originally "sandal" (see sole (n.1)), so called from resemblance of the fish to a sandal.

solecism --- 1577, from M.Fr. solécisme, from L. soloecismus "mistake in speaking or writing," from Gk. soloikismos "to speak (Greek) incorrectly," from soloikos "ungrammatical utterance," prop. "a speaking like the people of Soloi," from Soloi, Athenian colony in Cilicia, whose dialect the Athenians considered barbarous.

solemn --- c.1290, from O.Fr. solempne (Fr. solennel), from L. sollemnis "formal, ceremonial, traditional," perhaps related to sollus "whole" (see safe (adj.). Solemnize is recorded from 1382.

solenoid --- coil of insulated wire carrying an electrical current and having magnetic properties, 1827, from Fr. solénoïde, from Gk. solen "pipe, channel" + comb. form of eidos "form, shape" (see -oid).

sol-fa --- 1548, from It., from M.L. sol + fa, two notes of the musical scale. Related to solfeggio "use the sol-fa system" (1774), from It. solfeggiare (see gamut).

solicit --- c.1422, "to disturb, trouble," from M.Fr. soliciter, from L. solicitare "to disturb, rouse," from sollicitus "agitated," from sollus "whole, entire" + citus "aroused," pp. of ciere "shake, excite, set in motion" (see cite). Meaning "to further (business affairs)" evolved c.1450 from M.Fr. sense of "manage affairs." The sexual sense (often in ref. to prostitutes) is attested from 1701, probably from a merger of the business sense and an earlier sense of "to court or beg the favor of" (a woman), attested from 1591.

solicitor --- 1412, "one who urges," from M.Fr. soliciteur, from soliciter (see solicit). Meaning "one who conducts matters on behalf of another" is from c.1425. As a name for a specific class of legal practitioners in Britain, it is attested from 1577.

solicitous --- 1563, from L. sollicitus "restless, uneasy, careful" (see solicit).

solid (adj.) --- 1391, from O.Fr. solide "firm, dense, compact," from L. solidus "firm, whole, entire" (related to salvus "safe"), from PIE base *sol- "whole" (cf. Gk. holos "whole," L. salus "health;" see safe (adj.)). Slang sense of "wonderful, remarkable" first attested 1920 among jazz musicians. The noun is recorded from 1495. Solid South in U.S. political history is attested from 1858. Solidify is from 1799 (trans.), 1837 (intrans.). Solid state as a term in physics is recorded from 1953; meaning "employing transistors (as opposed to vacuum tubes)" is from 1959.

solidarity --- 1841, from Fr. solidarité "mutual responsibility," a coinage of the "Encyclopédie" (1765), from solidaire "interdependent, complete, entire," from solide (see solid). With a capital S-, the name of an independent trade union movement in Poland, formed Sept. 1980 and officially banned Oct. 1982, from Pol. Solidarnosc.

solidus --- 1387, pl. solidi, used of both Eng. shilling and Roman gold coin, from L.L. solidus, an imperial Roman coin (worth about 25 denarii), from nummus solidus, lit. "solid coin" (see solid).

solifidian --- one who believes in salvation by faith alone (based on Luther's translation of Rom. iii:28), 1596, Reformation coinage from L. solus "alone" + fides "faith" (see faith).

soliloquy --- 1604, from L.L. soliloquium "a talking to oneself," from L. solus "alone" + loqui "speak." First used in translation of L. "Liber Soliloquiorum," a treatise by Augustine, who is said to have coined the word, on analogy of Gk. monologia (see monologue). Verb soliloquize is recorded from 1759.

solipsism --- 1874, coined from L. solus "alone" + ipse "self." The view or theory that self is the only object of real knowledge or the only thing that is real.

solitaire --- 1716, "solitary person, recluse," from Fr. solitaire, from L. solitarius (see solitary). Sense of "a precious stone set by itself" is from 1727. Meaning "card game played by one person" is first attested 1746.

solitary --- c.1340, from O.Fr. solitaire, from L. solitarius "alone, lonely," from solitas "loneliness, solitude," from solus "alone" (see sole (adj.)).

solitude --- c.1374, from O.Fr. solitude "loneliness," from L. solitudinem (nom. solitudo) "loneliness," from solus "alone" (see sole (adj.)). "Not in common use in English until the 17th c." [OED]

solo --- 1695, "piece of music for one voice or instrument," from It. solo, lit. "alone," from L. solus "alone" (see sole (adj.)). The adj. is recorded from 1712; non-musical sense of "alone, unassisted" is attested from 1909. The verb is first attested 1886. Soloist is from 1864. Latin solus was used in stage directions (1599) and in phrases solus cum sola "alone with an unchaperoned woman" and solus cum solo "all on one's own," both lit. "alone with alone."

Solomon --- masc. proper name, Biblical name of David's son, king of Judah and Israel and wisest of all men, from Gk. Solomon, from Heb. Sh'lomoh, from shelomo "peaceful," from shalom "peace." The Arabic form is Suleiman. The common medieval form was Salomon (Vulgate, Tyndale, Douai); Solomon was used in Geneva Bible and KJV. Used allusively for "a wise ruler" since 1554.

solon --- legislator, 1625, from Gk. Solon, name of early lawgiver of Athens, one of the seven sages. Often (especially in U.S., where it is applied by journalists to Congressmen, township supervisors, etc.) with a tinge of sarcasm.

solstice --- c.1250, from O.Fr. solstice, from L. solstitium "point at which the sun seems to stand still," from sol "sun" (see sol) + pp. stem of sistere "to come to a stop, make stand still" (see assist).

soluble --- 1373, "capable of being dissolved," from M.Fr. soluble, from L.L. solubilis "that may be loosened or dissolved," from stem of L. solvere "loosen, dissolve" (see solve). Meaning "capable of being solved" is attested from 1705.

solution --- 1375, "a solving or being solved," from O.Fr. solucion, from L. solutionem (nom. solutio) "a loosening or unfastening," also "a solving," from pp. stem of solvere "to loosen, untie, solve, dissolve" (see solve). Meaning "liquid containing a dissolved substance" is first recorded 1594.

solve --- c.1440, "to disperse, dissipate, loosen," from L. solvere "to loosen, dissolve, untie," from PIE *se-lu-, from reflexive pronoun *swe- + base *leu- "to loosen, divide, cut apart" (cf. Gk. lyein "to loosen, release, untie," O.E. -leosan "to lose," leas "loose;" see lose). The meaning "explain, answer" is attested from c.1533; for sense evolution, see solution. Mathematical use is attested from 1737.

solvent (adj.) --- 1653, "able to pay all one owes," from Fr. solvent, from L. solventem (nom. solvens), prp. of solvere "loosen, dissolve" (see solve). Noun meaning "substance able to dissolve other substances" first recorded 1671.

solvitur ambulando --- an appeal to practical experience for a solution or proof, from L., lit. "(the problem) is solved by walking," originally in ref. to the proof by Diogenes the Cynic of the possibility of motion.

soma --- name of an intoxicant used in ancient Vedic ritual, prepared from the juice of some plant, from Skt. soma, from PIE *seu- "juice," from base *seue- "to take liquid" (see sup (2)). In "Brave New World" (1932), the name of a state-dispensed narcotic producing euphoria and hallucination.

somatic --- pertaining to the body, 1775, from Fr. somatique, from Gk. somatikos "of the body," from soma (gen. somatos) "body."

somber --- 1760 (earlier sombrous, c.1730), from Fr. sombre "dark, gloomy," from O.Fr. sombre, from L.L. subumbrare "to shadow," from sub "under" + umbra "shade, shadow," from PIE *andho- "blind, dark."

sombrero --- 1770, from Sp. sombrero "broad-brimmed hat," originally "umbrella or parasol" (1598), from sombra "shade," from L.L. subumbrare (see somber).

-some --- as a suffix forming adjectives, it represents O.E. -sum (see some; cf. O.Fris. -sum, Ger. -sam, O.N. -samr), related to sama "same." As a suffix added to numerals meaning "a group of that number" (cf. twosome) it represents O.E. sum "some," used after the genitive plural (cf. sixa sum "six-some"), the inflection disappearing in M.E. Use of some with a number meaning "approximately" also was in O.E.

some --- O.E. sum "some," from P.Gmc. *sumas (cf. O.S., O.Fris., O.H.G. sum, O.N. sumr, Goth. sums), from PIE base *sem- "one, as one" (cf. Skt. samah "even, level, similar, identical;" Gk. hamo-; see same).

somersault --- 1530, from M.Fr. sombresault, from O.Prov. sobresaut, from sobre "over" (from L. supra "over") + saut "a jump," from L. saltus, from the root of salire "to leap" (see salient). Sometimes further corrupted to somerset, etc.

somewhat --- c.1200, "a certain amount, to a certain degree," from some + what. Replaced O.E. sumdæl, sume dæle "somewhat, some portion," lit. "some deal."

somnambulism --- 1794 (as somnambulation), from Mod.L. somnambulus "sleepwalker," from L. somnus "sleep" (see somnolence) + ambulare "to walk" (see amble). Won out over noctambulation. To talk in one's sleep is somniloquence (1841).

somnolence --- c.1386, from O.Fr. sompnolence, from L. somnolentia "sleepiness," from somnolentus, from somnus "sleep," from PIE *swep-no, from base *swep- "sleep" (cf. Skt. svapnah, Avestan kvafna-, Gk. hypnos, Lith. sapnas, O.C.S. sunu, O.Ir. suan, Welsh hun "sleep," L. sopor "a deep sleep," O.E. swefn, O.N. svefn "a dream").

son --- O.E. sunu "son," from P.Gmc. *sunuz (cf. O.S., O.Fris. sunu, O.N. sonr, Dan. søn, Swed. son, M.Du. sone, Du. zoon, O.H.G. sunu, Ger. Sohn, Goth. sunus "son"), from PIE *sunu-/*sunyu- (cf. Skt. sunus, Gk. huios, Avestan hunush, Armenian ustr, Lith. sunus, O.C.S. synu, Rus., Pol. syn "son"), from root *su- "to give birth" (cf. Skt. sauti "gives birth," O.Ir. suth "birth, offspring"). Sonny as a familiar form of address to one younger or inferior is from 1870. Son of _____ as the title of a sequel to a book or movie is recorded from 1929.

son of a bitch --- 1707 as a direct phrase, but implied much earlier.

sonant --- 1846, from L. sonantem (nom. sonans), prp. of sonare "make a noise," related to sonus "sound" (see sound (n.1)).

sonar --- 1946, from first letters of "sound navigation ranging," on pattern of radar.

sonata --- 1694, from It. sonata "piece of instrumental music," lit. "sounded" (i.e. "played on an instrument," as opposed to cantata "sung"), fem. pp. of sonare "to sound," from L. sonare "to sound" (see sound (n.1)). Meaning narrowed by mid-18c. toward application to large-scale works in three or four movements.

song --- O.E. sang "art of singing, a metrical composition adapted for singing," from P.Gmc. *sangwaz (cf. O.N. söngr, Norw. song, Swed. sång, O.S., Dan., O.Fris., O.H.G., Ger. sang, M.Du. sanc, Du. zang, Goth. saggws), related to sing (q.v.). Songbook is O.E. sangboc; song-bird is from 1774; songster is O.E. sangystre. Phrase for a song is from "All's Well" III.ii.9. With a song in (one's) heart "feeling of joy" is first attested 1930 in Lorenz Hart's lyric. Song and dance as a form of vaudeville act is attested from 1872; fig. sense of "rigmarole" is from 1895.

sonic --- 1923, from L. sonus "sound" (see sound (n.1)). Sonic boom is attested from 1952.

sonnet --- 1557 (in title of Surrey's poems), from Fr. sonnet (1543) or directly from It. sonetto, lit. "little song," from O.Prov. sonet "song," dim. of son "song, sound," from L. sonus "sound" (see sound (n.1)). Originally in Eng. also "any short lyric poem;" precise meaning is from It., where Petrarch (14c.) developed a scheme of an eight-line stanza (rhymed abba abba) followed by a six-line stanza (cdecde, the Italian sestet, or cdcdcd, the Sicilian sestet). Shakespeare developed the English Sonnet for his rhyme-poor native tongue: three Sicilian quatrains followed by a heroic couplet (ababcdcdefefgg).

sonorous --- 1611, from L. sonorus "resounding," from sonor (gen. sonoris) "sound, noise," from sonare "to sound" (see sound (n.1)).

soon --- O.E. sona "at once, immediately," from W.Gmc. *sæno (cf. O.Fris. son, O.S. sana, O.H.G. san, Goth. suns "soon"). Sense shifted early M.E. to "within a short time" through human nature (cf. anon). Amer.Eng. Sooner for "Oklahoma native" is 1930, from the fact that in 1889 many settlers of the territory snuck onto public land and staked their claims "sooner" than the legal date and time.

soot --- O.E. sot, from P.Gmc. *sotam "soot" (cf. O.N. sot, O.Du. soet, N.Fris. sutt), lit. "what settles," from PIE *sodo- (cf. O.C.S. sazda, Lith. suodziai, O.Ir. suide, Bret. huzel "soot"), from base *sod-/*sed- "to sit" (see sedentary).

sooth --- O.E. soð "truth," noun use of soþ (adj.) "true," originally *sonþ-, from P.Gmc. *santhaz (cf. O.N. sannr, O.S. soth, O.H.G. sand "true," Goth. sunja "truth"), and thus cognate with O.E. synn "sin" and L. sontis "guilty" (truth is related to guilt via "being the one;" see sin), from PIE *es-ont- "being, existence," thus "real, true," from prp. of base *es-, the s-form of the verb "to be" (see be), preserved in L. sunt "they are" and Ger. sind. Archaic in Eng., it is the root of modern words for "true" in Swed. (sann) and Dan. (sand). In common use until c.1650, then obsolete until revived as an archaism early 19c. by Scott, etc. Soothsayer is attested from 1340, from O.E. seðan "declare (the truth)."

soothe --- O.E. soðian "show to be true," from soð "true" (see sooth). Sense of "quiet, comfort, mollify" is first recorded 1697, on notion of "to assuage one by asserting that what he says is true" (i.e. to be a yes-man), a sense attested from 1568.

sop --- O.E. sopp- "bread soaked in some liquid," (in soppcuppe "cup into which sops are put"), from P.Gmc. *suppo, related to O.E. verb suppan (see sup (2)), probably reinforced by O.Fr. soupe (see soup (n.)). Meaning "something given to appease" is from 1665, an allusion to the sop given by the Sibyl to Cerberus in Virgil's "Aeneid."

sopaipilla --- from Mexican Sp., ult. from O.Sp. sopa "food soaked in liquid," from a Gmc. source, from PIE *seue- "to take liquid" (see sup (2)).

Sophia --- fem. proper name, from Gk. sophia "wisdom," from sophos "wise."

sophism --- c.1350, "specious but fallacious argument," from O.Fr. sophime "a fallacy, false argument," from L. sophisma, from Gk. sophisma "sophism, clever device," from sophizesthai "become wise" (see sophist).

sophist --- 1542, earlier sophister (c.1380), from L. sophista, sophistes, from Gk. sophistes, from sophizesthai "to become wise or learned," from sophos "wise, clever," of unknown origin. Gk. sophistes came to mean "one who gives intellectual instruction for pay," and, contrasted with "philosopher," it became a term of contempt. Ancient sophists were famous for their clever, specious arguments.

sophistication --- c.1400, "use or employment of sophistry," from M.L. sophisticationem (nom. sophisticatio), from sophisticare "adulterate, cheat quibble," from L. sophisticus "of sophists," from Gk. sophistikos "of or pertaining to a sophist," from sophistes "a wise man, master, teacher" (see sophist). Meaning "wordly wisdom, refinement, discrimination" is attested from 1850; sophisticated (of persons) "worldly wise, discriminating, refined" is attested from 1895.

sophistry --- 1340, from O.Fr. sophistrie, from M.L. sophistria, from L. sophista, sophistes (see sophist).

Sophocles --- Athenian tragic poet (c.496-406 B.C.E.), the name is Gk. Sophokles, lit. "famed for wisdom," from sophos "wise" + *-kles "fame" (see Damocles).

sophomore --- 1688, "student in the second year of university study," lit. "arguer," altered from sophumer (1653, from sophume, archaic variant form of sophism), probably by influence of folk etymology derivation from Gk. sophos "wise" + moros "foolish, dull." Short form soph is attested from 1778. Sophomoric "characteristic of a sophomore" (regarded as self-assured and opinionated but crude and immature) is attested from 1837.

Sophronia --- fem. proper name, from Gk. sophronia, from sophron (gen. sophronos) "discreet, prudent," prop. "of sound mind," from sos "safe, sound, whole" + phren "midriff, heart, mind."

-sophy --- suffix meaning "knowledge," from O.Fr. -sophie, from L. -sophia, from Gk. -sophia, from sophia "skill, wisdom, knowledge," of unknown origin.

soporific --- 1690, from Fr. soporifique (1687), formed in Fr. from L. sopor (gen. soporis) "deep sleep," from a causative form of the PIE base *swep- "to sleep" (see somnolence).

sopping --- very wet, 1877, from sop (v.) "to drench with moisture" (1682), from sop (q.v.).

soppy --- very wet, 1823, from sop; meaning "sentimental" first recorded 1918.

soprano --- 1730, "the highest singing voice," from It. soprano "the treble in music," lit. "high," from sopra "above," from L. supra, fem. abl. sing. of super (see super-). Meaning "a singer having a soprano voice" is from 1738. Soprano saxophone is attested from 1859.

Sorb --- 1836 (implied in Sorbian), from Ger. Sorbe, from Slavic Serb, the national designation. Slavic people surviving in Lusatia, eastern Saxony, also known as Wends.

sorb --- fruit of the service tree, 1530, from Fr. sorbe, from L. sorbum "service-berry" (small, edible fruit of the European mountain ash), from sorbus, from PIE base *sor-/*ser- "red, reddish-brown." Hence sorbic acid (1815), so called because it was first isolated from these berries.

sorbet --- 1585, "cooling drink of fruit juice and water," from Fr. sorbet, probably from It. sorbetto, from Turk. serbet (see sherbet). Meaning "frozen dessert, sherbet" first recorded 1864.

Sorbonne --- 1560, from Sorbon, place name in the Ardennes. Theological college in Paris founded early 13c. by Robert de Sorbon (b.1201), chaplain and confessor of Louis IX.

sorcery --- c.1300, from O.Fr. sorcerie, from sorcier "sorcerer," from V.L. *sortiarius, lit. "one who influences, fate, fortune," from L. sors (gen. sortis) "lot, fate, fortune" (see sort). Sorceress (c.1384) is attested much earlier than sorcerer (1526).

sordid --- 1584, "festering," from L. sordidus "dirty," from sordere "be dirty, be shabby," related to sordes "dirt," from PIE base *swordo- "black, dirty" (cf. Goth. swarts, O.E. sweart "black"). Sense of "foul, low, mean" first recorded 1611.

sore (adj.) --- O.E. sar "painful, grievous, aching," infl. in meaning by O.N. sarr "sore, wounded," from P.Gmc. *sairaz (cf. O.Fris. sar "painful," M.Du. seer, Du. zeer "sore, ache," O.H.G. ser "painful"), from PIE base *sai- "suffering" (cf. O.Ir. saeth "pain, sickness"). Adv. use (e.g. sore afraid) has mostly died out (except as sorely), but remains the main meaning of Ger. cognate sehr "very." Slang meaning "angry, irritated" is first recorded 1738; sorehead "mean, discontented person" is first recorded 1848, Amer.Eng.

sore (n.) --- O.E. sar "bodily injury, sickness, disease, pain, suffering," from root of sore (adj.). Now restricted to ulcers, boils, blisters.

sorghum --- 1597, "Indian millet," from Mod.L. Sorghum, the genus name, from It. sorgo "a tall cereal grass," probably from M.L. surgum, suricum (12c.), perhaps a variant of L. syricum "Syrian," as in Syricum (gramen) "(grass) of Syria," from Syria, a possible source of the plant or its grain in ancient times.

Soroptimist --- international society of business women and women executives, first club formed 1921 in Oakland, Calif., U.S., from sorority + optimist, probably after the Optimist Club.

sorority --- 1532, "body of women united for some purpose," from M.L. sororitas "sisterhood, of or pertaining to sisters," from L. soror "sister" (see sister). OED 2nd ed. lists first reference for sense of "women's society in a college or university" as c.1900, but they existed at least 20 years before this.

sorrel (adj.) --- reddish brown, c.1430, from M.Fr. sorel, from sor "yellowish-brown," probably from Frankish *saur "dried" (cf. M.Du. soor "dry," O.H.G. soren "to become dry," O.E. sear "withered, barren;" see sere). Perhaps a diminutive form.

sorrel (n.) --- small perennial plant, c.1400, from O.Fr. surele (12c.), from sur "sour," from Frankish *sur (cf. O.H.G., O.E. sur "sour;" see sour). So called for the taste of its leaves.

sorrow (n.) --- O.E. sorg "grief, regret, trouble, care," from P.Gmc. *surgo (cf. O.S. sorga, O.N. sorg, M.Du. sorghe, Du. zorg, O.H.G. soraga, Ger. sorge, Goth. saurga), perhaps from PIE *swergh- (cf. Skt. surksati "cares for," Lith. sergu "to be sick," O.C.S. sraga "sickness," O.Ir. serg "sickness"). The verb is O.E. sorgian.

sorry --- O.E. sarig "distressed, full of sorrow," from W.Gmc. *sairig-, from *sairaz "pain" (physical and mental); related to sar (see sore). Meaning "wretched, worthless, poor" first recorded c.1250. Spelling shift from -a- to -o- by influence of sorrow. Apologetic sense (short for I'm sorry) is attested from 1834; phrase sorry about that popularized 1960s by U.S. TV show "Get Smart."

sort (n.) --- c.1380, from O.Fr. sorte "class, kind," from L. sortem (nom. sors) "lot, fate, share, portion, rank, category," from PIE base *ser- "to line up" (cf. L. serere "to arrange, attach, join;" see series). The sense evolution in V.L. is from "what is allotted to one by fate," to "fortune, condition," to "rank, class, order." Out of sorts "not in usual good condition" is attested from 1621, with lit. sense of "out of stock."

sort (v.) --- 1358, "to arrange according to type or quality," from O.Fr. sortir "allot, sort, assort," from L. sortiri "draw lots, divide, choose," from sors (see sort (n.)). In some senses, the verb is a shortened form of assort.

sortie --- attack of the besieged upon the besiegers, 1778, from Fr. sortie, lit. "a going out," noun use of fem. pp. of sortir "go out," from O.Fr., "to go out, escape," from V.L. *surctire, from pp. of L. surgere "rise up" (see surge).

SOS --- 1910, from International Morse code letters, chosen arbitrarily as being easy to transmit and difficult to mistake. Not an acronym for "save our ship" or anything else. Won out over alternate suggestion C.Q.D., which is said to mean "come quickly, distress," or "CQ," general call for alerting other ships that a message follows, and "D" for danger. SOS is the telegraphic distress signal only; the oral equivalent is mayday.