The first three dominant cusps, taken collectively, of a lower molar tooth. ... See: trigone. ... Origin: see trigonum ... (05 Mar 2000) ... 
Type: Term Pronunciation: trī-gon′id, -gō′nid Definitions: 1. The first three dominant cusps, taken collectively, of a lower molar tooth.
trigonid The first three dominant cusps, taken collectively, of a lower molar tooth.