os sesamoideum vs sesamoid

os sesamoideum and sesamoid both are nouns.

Word	Noun	Adjective	Verb	Adverb
os sesamoideum	Yes	No	No	No
sesamoid	Yes	No	No	No

As nouns, os sesamoideum and sesamoid are synonyms defined as:

os sesamoideum and sesamoid: any of several small round bones formed in a tendon where it passes over a joint

Other synonyms of os sesamoideum include sesamoid bone.

os sesamoideum (noun)	sesamoid (noun)
any of several small round bones formed in a tendon where it passes over a joint	any of several small round bones formed in a tendon where it passes over a joint