omnivore vs fauna

omnivore and fauna both are nouns.

Word	Noun	Adjective	Verb	Adverb
omnivore	Yes	No	No	No
fauna	Yes	No	No	No

As nouns, fauna is a hypernym of omnivore; that is, fauna is a word with a broader meaning than omnivore:

Other hypernyms of omnivore include animal, animate being, beast, brute, creature.

omnivore (noun)	fauna (noun)
an animal that feeds on both animal and vegetable substances	a living organism characterized by voluntary movement
a person who eats all kinds of foods	all the animal life in a particular region or period