γομφ-ίος · gomph-ios — LSJ
grinder-tooth, molar, chiefly in pl., Hp. Epid. 5.100, Hdt. 9.83, Ar. Pax 34, etc.; ψοφεῖ δʼ ὁ γ. Epich. 21; γομφίους συγκρούων with his teeth chattering, Babr. 92.8; opp. προσθίος, X. Mem. 1.4.6, Arist. PA 661b8.
tooth of a key, Ar. Th. 423.