oilbird vs caprimulgiform bird

oilbird and caprimulgiform bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
oilbird	Yes	No	No	No
caprimulgiform bird	Yes	No	No	No

As nouns, caprimulgiform bird is a hypernym of oilbird; that is, caprimulgiform bird is a word with a broader meaning than oilbird:

oilbird: nocturnal fruit-eating bird of South America that has fatty young yielding an oil that is used instead of butter
caprimulgiform bird: long-winged nonpasserine birds

oilbird (noun)	caprimulgiform bird (noun)
nocturnal fruit-eating bird of South America that has fatty young yielding an oil that is used instead of butter	long-winged nonpasserine birds