alertyoudaoicibaDictYouDict[alert 词源字典]
alert: [17] Alert comes, via French, from an Italian phrase all’ erta ‘on the look-out’, or literally ‘at the (alla) watch-tower (erta)’. Erta was short for torre erta, literally ‘high tower’, in which the adjective erta ‘high’ came ultimately from Latin ērectus, the past participle of ērigere ‘raise’.
=> erect[alert etymology, alert origin, 英语词源]
alert (adv.)youdaoicibaDictYouDict
"on the watch," 1590s, from French alerte "vigilant" (17c.), from phrase à l'erte "on the watch," from Italian all'erta "to the height," from erta "lookout, high tower," noun use of fem. of erto, past participle of ergere "raise up," from Latin erigere "raise" (see erect). The adjective is attested from 1610s, the noun from 1803, and the verb from 1868. Related: Alerted; alerting.