tightyoudaoicibaDictYouDict[tight 词源字典]
tight: [14] Tight originally meant ‘dense’ (‘His squire rode all night in a wood that was full tight’, Torrent of Portugal 1435). It appears to have been an alteration of an earlier thight ‘dense, thickset’, which was borrowed from Old Norse théttr ‘watertight, dense’. And this, like German and Dutch dicht ‘dense, close’, came from a prehistoric Germanic *thingkhtaz, whose other relatives include Lithuanian tankus ‘thick, standing close together’, Irish contēcim ‘coagulate’, and Sanskrit tañc- ‘contract’. The sense ‘firmly fixed’ developed in the 16th century, ‘drunk’ in the 19th century.
[tight etymology, tight origin, 英语词源]
tight (adj.)youdaoicibaDictYouDict
c. 1400, tyght "dense, close, compact," from Middle English thight, from Old Norse þettr "watertight, close in texture, solid," and also from Old English -þiht (compare second element in meteþiht "stout from eating"), both from Proto-Germanic *thinhta- (cognates: Middle High German dihte "dense, thick," German dicht "dense, tight," Old High German gidigan, German gediegen "genuine, solid, worthy"), from PIE root *tenk- (2) "to become firm, curdle, thicken" (cognates: Irish techt "curdled, coagulated," Lithuanian tankus "close, tight," Persian tang "tight," Sanskrit tanakti "draws together, contracts").

Sense of "drawn, stretched" is from 1570s; meaning "fitting closely" (as of garments) is from 1779; that of "evenly matched" (of a contest, bargain, etc.) is from 1828, American English; that of "drunk" is from 1830. Of persons, "close, intimate, sympathetic" from 1956. From 1670s as an adverb; to sit tight is from 1738; sleep tight as a salutation in sending someone off to bed is by 1871. Related: Tightly; tightness. Tight-assed "unwilling to relax" is attested from 1903. Tight-laced is recorded from 1741 in both the literal and figurative senses. Tight-lipped is first attested 1872.