warbler vs oscine bird

warbler and oscine bird both are nouns.

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

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

Other hypernyms of warbler include oscine.

warbler (noun)	oscine bird (noun)
a small active songbird	passerine bird having specialized vocal apparatus
a singer; usually a singer who adds embellishments to the song