oscine bird vs passeriform bird

oscine bird and passeriform bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
oscine bird	Yes	No	No	No
passeriform bird	Yes	No	No	No

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

oscine bird: passerine bird having specialized vocal apparatus
passeriform bird: perching birds mostly small and living near the ground with feet having 4 toes arranged to allow for gripping the perch; most are songbirds; hatchlings are helpless

Other hypernyms of oscine bird include passerine.

oscine bird (noun)	passeriform bird (noun)
passerine bird having specialized vocal apparatus	perching birds mostly small and living near the ground with feet having 4 toes arranged to allow for gripping the perch; most are songbirds; hatchlings are helpless