jayyoudaoicibaDictYouDict[jay 词源字典]
jay: [13] Like the robin, the jay may have been christened originally with a human name; Latin Gaius. At all events, the term for it in postclassical Latin was gaius, which passed into English via Old French jay. The term jaywalker for ‘one who crosses the road illegally’ originated in the USA around the time of World War I; it was based on an American use of jay for a ‘fool’ or ‘simpleton’.
[jay etymology, jay origin, 英语词源]
jay (n.)youdaoicibaDictYouDict
c. 1300, common European bird (Garrulus glandarinus), from Old North French gai, Old French jai "magpie, jay," from Late Latin gaius "a jay," probably echoic and supposedly influenced by Latin Gaius, a common Roman proper name. For other bird names from proper names, compare martin and parrot. Applied to the North American blue jay (Cyanocitta cristata) from 1709. Applied to humans in sense of "impertinent chatterer, flashy dresser" from 1620s.
jay (adj.)youdaoicibaDictYouDict
"fourth-rate, worthless" (as in a jay town), 1888, American English, apparently from some disparaging sense of jay (n.). Perhaps from a decaying or ironical use of jay "flashy dresser."