bonnet (n.)youdaoicibaDictYouDict[bonnet 词源字典]
late 14c., Scottish bonat "brimless hat for men," from Old French bonet, short for chapel de bonet, from bonet (12c., Modern French bonnet) "kind of cloth used as a headdress," from Medieval Latin bonitum "material for hats," perhaps a shortening of Late Latin abonnis "a kind of cap" (7c.), which is perhaps from a Germanic source. [bonnet etymology, bonnet origin, 英语词源]