gill slit vs bodily structure

gill slit and bodily structure both are nouns.

Word	Noun	Adjective	Verb	Adverb
gill slit	Yes	No	No	No
bodily structure	Yes	No	No	No

As nouns, bodily structure is a hypernym of gill slit; that is, bodily structure is a word with a broader meaning than gill slit:

gill slit: one of a series of slit openings in the pharynxes of fishes and aquatic amphibians through which water passes
bodily structure: a particular complex anatomical part of a living thing and its construction and arrangement

Other hypernyms of gill slit include anatomical structure, body structure, complex body part, structure.

gill slit (noun)	bodily structure (noun)
one of a series of slit openings in the pharynxes of fishes and aquatic amphibians through which water passes	a particular complex anatomical part of a living thing and its construction and arrangement