internal nostril vs naris

internal nostril and naris both are nouns.

Word	Noun	Adjective	Verb	Adverb
internal nostril	Yes	No	No	No
naris	Yes	No	No	No

As nouns, naris is a hypernym of internal nostril; that is, naris is a word with a broader meaning than internal nostril:

internal nostril: either one of the two posterior openings at the back of the nasal cavity leading to the nasopharynx
naris: any of the openings to the nasal cavities that allow air to flow through the cavities to the pharynx

internal nostril (noun)	naris (noun)
either one of the two posterior openings at the back of the nasal cavity leading to the nasopharynx	any of the openings to the nasal cavities that allow air to flow through the cavities to the pharynx