bullbat vs nightjar

bullbat and nightjar both are nouns.

Word	Noun	Adjective	Verb	Adverb
bullbat	Yes	No	No	No
nightjar	Yes	No	No	No

As nouns, nightjar is a hypernym of bullbat; that is, nightjar is a word with a broader meaning than bullbat:

bullbat: mainly nocturnal North American goatsucker
nightjar: mainly crepuscular or nocturnal nonpasserine birds with mottled greyish-brown plumage and large eyes; feed on insects

Other hypernyms of bullbat include caprimulgid, goatsucker.

bullbat (noun)	nightjar (noun)
mainly nocturnal North American goatsucker	mainly crepuscular or nocturnal nonpasserine birds with mottled greyish-brown plumage and large eyes; feed on insects