- vital[vital 词源字典]
- vital:  Vital comes via Old French vital from Latin vītālis. This was a derivative of vīta ‘life’. And vīta went back ultimately to Latin vīvus ‘living’, source of English vivacious, vivid, etc. Viable  is also descended from vīta, and etymologically means ‘capable of life’.
=> viable, vitamin, vivid[vital etymology, vital origin, 英语词源]
- vital (adj.)
- late 14c., "of or manifesting life," from Latin vitalis "of or belonging to life," from vita "life," related to vivere "to live," from PIE root *gweie- (1) "to live" (see bio-). The sense of "necessary or important" is from 1610s, via the notion of "essential to life" (late 15c.). Vital capacity recorded from 1852. Related: Vitally.