songster vs oscine

songster and oscine both are nouns.

Word	Noun	Adjective	Verb	Adverb
songster	Yes	No	No	No
oscine	Yes	Yes	No	No

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

Other hypernyms of songster include oscine bird.

songster (noun)	oscine (noun)
any bird having a musical call	passerine bird having specialized vocal apparatus
a person who sings with skill
a composer of words or music for popular songs

songster (adjective)	oscine (adjective)
	of or relating to the songbirds