protoconid

pro·to·co·nid

(prō'tō-ko'nid), The mesiolingual cusp of a lower molar tooth in a mammal.

pro·to·co·nid

(prō'tō-kon'id) 1. The mesiobuccal cusp of human lower molars. 2. The first lower molar cusp to develop evolutionarily.
See also: protocone[protocone + -id]

pro·to·co·nid

(prō'tō-kon'id) Mesiolingual cusp of mammalian lower molar tooth. [protocone + -id]