retreatyoudaoicibaDictYouDict[retreat 词源字典]
retreat: [14] Retreat and retract [15] are ultimately the same word. Both go back to Latin retrahere ‘draw back’, a compound verb formed from the prefix re- ‘back’ and trahere ‘draw, pull’ (source of English tractor). This passed into Old French as retraire, and its past participle retrait came to be used as a noun meaning ‘withdrawal’ – whence English retreat. Meanwhile the past participle of retrahere, retractus, had been used as the basis of a new Latin verb, retractāre, which passed into English via Old French retracter as retract.
=> contract, distract, retract, tractor[retreat etymology, retreat origin, 英语词源]
retreat (n.)youdaoicibaDictYouDict
c. 1300, "a step backward;" late 14c., "act of retiring or withdrawing; military signal for retiring from action or exercise," from Old French retret, noun use of past participle of retrere "draw back," from Latin retrahere "draw back, withdraw, call back," from re- "back" (see re-) + trahere "to draw" (see tract (n.1)). Meaning "place of seclusion" is from early 15c.; sense of "establishment for mentally ill persons" is from 1797. Meaning "period of retirement for religious self-examination" is from 1756.
retreat (v.)youdaoicibaDictYouDict
early 15c., "to draw in, draw back, leave the extremities," from retreat (n.) and in part from Old French retret, past participle of retrere. Meaning "to fall back from battle" is mid-15c. Related: Retreated; retreating.