古フランス語の jai, magpie, jay から、ラテン語の gaius, jay から、おそらく擬音語から。派生語源はおしゃべりな人、無作法な人。
英語の語源
jay
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 (n.)
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.)
"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."
例文
1. Jay had always tended to keep his girlfriends at a distance.
ジェイは一貫して彼女たちと距離を置いている。
2.I thought at first that Jay had been stirring things up.