whirligig (n.)youdaoicibaDictYouDict[whirligig 词源字典]
mid-15c., a child's toy, from whirl (v.) + gig (see gig (n.1)). Meaning "anything in constant motion" is from 1580s; "fickle, flighty person" is from c. 1600; as a type of water beetle, from 1713.[whirligig etymology, whirligig origin, 英语词源]