brad (n.)youdaoicibaDictYouDict[brad 词源字典]
"small wire nail," late 13c., brod, from Old Norse broddr "spike, point, arrow," from Proto-Germanic *brozda- (cognates: Old English brord "point, prick, blade of grass," Old High German brort "point, edge, crown"), from PIE *bhrs-dh-, from root *bhars- "projectile, point, bristle" (see bristle (n.)).[brad etymology, brad origin, 英语词源]