twigyoudaoicibaDictYouDict[twig 词源字典]
twig: English has two separate words twig. The older, ‘small branch’ [OE], which has relatives in German zweig and Dutch tijg, appears to have been formed from the Germanic base *twi- ‘two’, and so etymologically it presumably denotes a ‘forked branch’. The origins of twig ‘catch on, understand’ [18] are uncertain. It may be the same word as the contemporary but now defunct twig ‘pull’. This was presumably related to tweak [17] and twitch [12], which go back to a prehistoric Germanic base *twik-.
=> tweak, twitch, two[twig etymology, twig origin, 英语词源]
twig (n.)youdaoicibaDictYouDict
Old English twig "twig, branch, shoot, small tree," from Proto-Germanic *twigga "a fork" (cognates: Middle Dutch twijch, Dutch twijg, Old High German zwig, German Zweig "branch, twig"), from PIE *dwi-ko-, from *dwo- "two" (see two). Compare Old English twisel "fork, point of division."