soulless (adj.)youdaoicibaDictYouDict[soulless 词源字典]
Old English sawolleas "dead, lifeless;" see soul (n.1) + -less. Modern use (1550s) likely is a re-formation.[soulless etymology, soulless origin, 英语词源]
soulmate (n.)youdaoicibaDictYouDict
1822 (as soul mate), first attested in Coleridge, from soul (n.1) + mate (n.). One-word form is from early 20c.
sound (n.1)youdaoicibaDictYouDict
"noise, what is heard, sensation produced through the ear," late 13c., soun, from Old French son "sound, musical note, voice," from Latin sonus "sound, a noise," from PIE *swon-o-, from root *swen- "to sound" (cognates: Sanskrit svanati "it sounds," svanah "sound, tone;" Latin sonare "to sound;" Old Irish senim "the playing of an instrument;" Old English geswin "music, song," swinsian "to sing;" Old Norse svanr, Old English swan "swan," properly "the sounding bird").

The terminal -d was established c. 1350-1550 as part of a tendency to add -d- after -n-. First record of sound barrier is from 1939. Sound check is from 1977; sound effects is 1909, originally live accompaniments to silent films.
The experts of Victor ... will ... arrange for the synchronized orchestration and sound effects for this picture, in which airplane battles will have an important part. ["Exhibitor's Herald & Moving Picture World," April 28, 1928]
sound (adj.)youdaoicibaDictYouDict
"free from special defect or injury," c. 1200, from Old English gesund "sound, safe, having the organs and faculties complete and in perfect action," from Proto-Germanic *sunda-, from Germanic root *swen-to- "healthy, strong" (cognates: Old Saxon gisund, Old Frisian sund, Dutch gezond, Old High German gisunt, German gesund "healthy," as in the post-sneezing interjection gesundheit; also Old English swið "strong," Gothic swinþs "strong," German geschwind "fast, quick"), with connections in Indo-Iranian and Balto-Slavic. Meaning "right, correct, free from error" is from mid-15c. Meaning "financially solid or safe" is attested from c. 1600; of sleep, "undisturbed," from 1540s. Sense of "holding accepted opinions" is from 1520s.
sound (v.2)youdaoicibaDictYouDict
"fathom, probe, measure the depth of," mid-14c. (implied in sounding), from Old French sonder, from sonde "sounding line," perhaps from the same Germanic source that yielded Old English sund "water, sea" (see sound (n.2)). Barnhart dismisses the old theory that it is from Latin subundare. Figurative use from 1570s.
sound (n.2)youdaoicibaDictYouDict
"narrow channel of water," c. 1300, from Old Norse sund "a strait, swimming," or from cognate Old English sund "act of swimming, stretch of water one can swim across, a strait of the sea," both from Proto-Germanic *sundam-, from *swum-to-, suffixed form of Germanic root *swem- "to move, stir, swim" (see swim (v.)).
sound (v.1)youdaoicibaDictYouDict
early 13c., sounen "to be audible, produce vibrations affecting the ear," from Old French soner (Modern French sonner) and directly from Latin sonare "to sound" (see sonata). From late 14c. as "cause something (an instrument, etc.) to produce sound." Related: Sounded; sounding.
sound-proof (adj.)youdaoicibaDictYouDict
1853, from sound (n.1) + proof (n.).
Soundex (n.)youdaoicibaDictYouDict
phonetic coding system, 1959, from sound (n.1) + brand-name suffix -ex.
soundless (adj.)youdaoicibaDictYouDict
c. 1600 from sound (n.1) + -less. Related: Soundlessly; soundlessness.
soundly (adv.)youdaoicibaDictYouDict
c. 1400, "safely;" also "deeply" (of sleep), from sound (adj.) + -ly (2). From 1570s as "thoroughly."
soundness (n.)youdaoicibaDictYouDict
late 14c., from sound (adj.) + -ness.
soundtrack (n.)youdaoicibaDictYouDict
1929, from sound (n.1) + track (n.).
soup (n.)youdaoicibaDictYouDict
"liquid food," 1650s, from French soupe "soup, broth" (13c.), from Late Latin suppa "bread soaked in broth," from a Germanic source (compare Middle Dutch sop "sop, broth"), from Proto-Germanic *sup-, from PIE *sub-, from root *seue- (2) "to take liquid" (see sup (v.2)).

Primordial soup is from a concept first expressed 1929 by J.B.S. Haldane. Soup to nuts "everything" is from 1910. Soup-kitchen, "public establishment supported by voluntary contributions, for preparing and serving soup to the poor at no cost" is attested from 1839. In Ireland, souper meant "Protestant clergyman seeking to make proselytes by dispensing soup in charity" (1854).
soup (v.)youdaoicibaDictYouDict
"increase the horsepower of an engine," 1921, probably from soup (n.) in slang sense of "narcotic injected into horses to make them run faster" (1911), influenced by supercharge (v.).
soupcon (n.)youdaoicibaDictYouDict
"a slight trace or suggestion," 1766, from French soupçon "suspicion," from Old French sospeçon "suspicion, worry, anxiety" (12c.), from Late Latin suspectionem (see suspicion).
soupy (adj.)youdaoicibaDictYouDict
"like soup; wet," 1828 (noted then as a Yorkshire word), from soup (n.) + -y (2). Related: Soupiness.
sour (adj.)youdaoicibaDictYouDict
Old English sur "sour, tart, acid, fermented," from Proto-Germanic *sura- "sour" (cognates: Old Norse surr, Middle Dutch suur, Dutch zuur, Old High German sur, German Sauer), from PIE root *suro- "sour, salty, bitter" (cognates: Old Church Slavonic syru, Russian syroi "moist, raw;" Lithuanian suras "salty," suris "cheese").

Meaning "having a peevish disposition" is from early 13c. Sense in whisky sour (1885) is "with lemon added" (1862). Sour cream is attested from 1855. French sur "sour, tart" (12c.) is a Germanic loan-word.
sour (v.)youdaoicibaDictYouDict
c. 1300, from sour (adj.). Compare Old High German suren, German säuern. Related: Soured; souring.
sourball (n.)youdaoicibaDictYouDict
1900 as "constantly grumbling person;" 1914 as a type of candy; from sour (adj.) + ball (n.1).