'mentum' definitions:

Definition of 'mentum'

(from WordNet)
noun
A projection like a chin formed by the sepals and base of the column in some orchids
noun
The protruding part of the lower jaw [syn: chin, mentum]
noun
A projection below the mouth of certain mollusks that resembles a chin

Definition of 'mentum'

From: GCIDE
  • mentum \men"tum\, n. [L., chin.] (Zool.) The front median plate of the labium in insects. See Labium. [1913 Webster]