mentum vs body part

mentum and body part both are nouns.

Word	Noun	Adjective	Verb	Adverb
mentum	Yes	No	No	No
body part	Yes	No	No	No

As nouns, body part is a hypernym of mentum; that is, body part is a word with a broader meaning than mentum:

mentum: a projection below the mouth of certain mollusks that resembles a chin
body part: any part of an organism such as an organ or extremity

mentum (noun)	body part (noun)
a projection below the mouth of certain mollusks that resembles a chin	any part of an organism such as an organ or extremity
the protruding part of the lower jaw
a projection like a chin formed by the sepals and base of the column in some orchids