type of sea fish, late 13c., probably from Old English haca "a hook, door-fastening" (related to hacod "pike" the fish), or from cognate Old Norse haki "hook;" in either case the fish so called from the shape of its jaw; both from Proto-Germanic *hakan (cognate with Dutch hake "hook"), from PIE root *keg- "hook, tooth" (see hook (n.)).