gagtooth

English dialect gag to project, stick out (of Scandinavian origin; akin to Old Norse gag hals having the head thrown back, Icelandic gagur bent backward, turned askew, Norwegian gag bent back, gaga to bend back) + tooth; akin to Old English gēagl throat, jaws, Middle High German gagen to fidget and perhaps to Old English geonian, ginian to yawn