SemeleyoudaoicibaDictYouDict[Semele 词源字典]
daughter of Cadmus and mother of Dionysus, from Latin, from Greek Semele, a Thraco-Phrygian earth goddess, from Phrygian Zemele "mother of the earth," probably cognate with Old Church Slavonic zemlja "earth," Latin humus "earth, ground, soil" (see chthonic).[Semele etymology, Semele origin, 英语词源]
semen (n.)youdaoicibaDictYouDict
late 14c., from Latin semen "seed of plants, animals, or men; race, inborn characteristic; posterity, progeny, offspring," figuratively "origin, essence, principle, cause," from PIE *si-so-, reduplication of root *se- (1) "to sow" (cognates: Latin serere "to sow," Old Prussian semen "seed," Lithuanian semens "seed of flax," Old Church Slavonic seme, Old High German samo "seed," German Same; see sow (v.)).
semester (n.)youdaoicibaDictYouDict
1827, from German Semester "half-year course in a university," from Latin semestris, in cursus semestris "course of six months," from semestris, semenstris "of six months, lasting six months, half-yearly, semi-annual," from sex "six" (see six) + mensis "month" (see moon (n.)). Related: Semestral; semestrial.
semi-youdaoicibaDictYouDict
before vowels sem-, word-forming element meaning "half, part, partly; partial, imperfect; twice," from Latin semi- "half," from PIE *semi- "half" (cognates: Sanskrit sami "half," Greek hemi- "half," Old English sam-, Gothic sami- "half").

Old English cognate sam- was used in such compounds as samhal "poor health," literally "half-whole;" samsoden "half-cooked," figuratively "stupid" (compare half-baked); samcucu "half-dead," literally "half-alive;" and the last survivor of the group, sandblind "dim-sighted" (q.v.). Common in Latin (as in semi-gravis "half-drunk," semi-hora "half hour," semi-mortuus "half-dead," semi-nudus "half-naked," semi-vir "half-man, hermaphrodite"). The Latin-derived form in English has been active in forming native words since 15c.
semi-annual (adj.)youdaoicibaDictYouDict
also semiannual, 1775, from semi- + annual. Related: Semiannually.
semi-arid (adj.)youdaoicibaDictYouDict
also semiarid, 1886, from semi- + arid.
semi-automatic (adj.)youdaoicibaDictYouDict
1853, from semi- + automatic (adj.). In reference to firearms, 1889.
semi-demi-youdaoicibaDictYouDict
word-forming element meaning "sixty-fourth part," 1660s; see semi- + demi-.
semi-detached (adj.)youdaoicibaDictYouDict
in reference to houses, 1845, from semi- + past participle of detach (v.).
The "Detached House" bears its peculiar characteristic on its front; it stands alone, and nothing more can be said about it; but with the "semi-detached house" there is a subtle mystery, much to be marvelled at. Semi-detached! Have the party-walls between two houses shrunk, or is there a bridge connecting the two, as in Mr. Beckford's house in Landsdown Crescent, Bath? A semi-detached house may be a house with a field on one side and a bone-boiling factory on the other. Semi-detached may mean half-tumbling to pieces. I must inquire into it. ["Houses to Let," in "Household Words," March 20, 1852]
semi-monthly (adj.)youdaoicibaDictYouDict
also semimonthly, 1809, from semi- + monthly.
semi-official (adj.)youdaoicibaDictYouDict
1798, from semi- + official (adj.). Related: Semi-officially.
semi-permeable (adj.)youdaoicibaDictYouDict
1873, from semi- + permeable. Translating German halbdurchlässig.
semi-professional (adj.)youdaoicibaDictYouDict
1824, from semi- + professional (adj.). As a noun from 1843. Related: Semi-professionally.
semi-solid (adj.)youdaoicibaDictYouDict
1803, from semi- + solid (adj.).
semi-trailer (n.)youdaoicibaDictYouDict
also semitrailer, 1910 in reference to motor vehicles (late 19c. in botany), from semi- + trailer.Short form semi is attested from 1942.
semi-weekly (adj.)youdaoicibaDictYouDict
also semiweekly, "occurring twice a week," 1791, from semi- + weekly.
semicircle (n.)youdaoicibaDictYouDict
1520s, from semi- + circle (n.) or else from Latin semicirculus.
semicircular (adj.)youdaoicibaDictYouDict
early 15c., from Latin semicirculus (see semicircle) + -ar.
semicolon (n.)youdaoicibaDictYouDict
punctuation-mark, 1640s, a hybrid coined from Latin-derived semi- + Greek-based colon (n.1). The mark itself was (and is) in Greek the point of interrogation.
semiconductor (n.)youdaoicibaDictYouDict
1838, "material whose electrical conductivity is between that of a conductor and that of an insulator," from semi- + conductor. Modern very specific sense is recorded from 1931.