thinyoudaoicibaDictYouDict[thin 词源字典]
thin: [OE] Thin denotes etymologically ‘stretched’. It goes back ultimately to the Indo- European base *ten- ‘stretch’, which also produced Latin tenuis ‘thin’ (source of English tenuous) and Latin tendere ‘stretch’ (source of English tend, tense, etc). From this was descended prehistoric Germanic *thunnuz, which has evolved into German dünn, Dutch dun, Swedish tunn, Danish tynd, and English thin.
=> tend, tense, tenuous[thin etymology, thin origin, 英语词源]
thin (adj.)youdaoicibaDictYouDict
Old English þynne "narrow, lean, scanty, not dense; fluid, tenuous; weak, poor," from Proto-Germanic *thunni "thin" (cognates: West Frisian ten, Middle Low German dunne, Middle Dutch dunne, Dutch dun, Old High German dunni, German dünn, Old Norse þunnr, Swedish tunn, Danish tynd), from PIE *tnu- "stretched, stretched out" (hence "thin"), from root *ten- "to stretch" (cognates: Latin tenuis "thin, slender;" see tenet).
These our actors ... were all Spirits, and Are melted into Ayre, into thin Ayre. [Shakespeare, "The Tempest," IV.i.150, 1610]
"Loose or sparse," hence "easily seen through," with figurative extensions. Related: Thinly; thinness. Thin-skinned is attested from 1590s; the figurative sense of "touchy" is from 1670s.
thin (v.)youdaoicibaDictYouDict
Old English þynnian "to make thin, lessen, dilute," also intransitive, "become thin," from thin (adj.). Intransitive sense of "to become less numerous" is attested from 1743; that of "to become thinner" is recorded from 1804. Compare similarly formed German dünnen, Dutch dunnen. Related: Thinned; thinning.