gastrocolic omentum vs omentum

gastrocolic omentum and omentum both are nouns.

Word	Noun	Adjective	Verb	Adverb
gastrocolic omentum	Yes	No	No	No
omentum	Yes	No	No	No

As nouns, omentum is a hypernym of gastrocolic omentum; that is, omentum is a word with a broader meaning than gastrocolic omentum:

gastrocolic omentum: part of the peritoneum attached to the stomach and to the colon and covering the intestines
omentum: a fold of peritoneum supporting the viscera

gastrocolic omentum (noun)	omentum (noun)
part of the peritoneum attached to the stomach and to the colon and covering the intestines	a fold of peritoneum supporting the viscera