yellow warbler vs wood warbler

yellow warbler and wood warbler both are nouns.

Word	Noun	Adjective	Verb	Adverb
yellow warbler	Yes	No	No	No
wood warbler	Yes	No	No	No

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

yellow warbler: yellow-throated American wood warbler
wood warbler: small bright-colored American songbird with a weak unmusical song

Other hypernyms of yellow warbler include New World warbler.

yellow warbler (noun)	wood warbler (noun)
yellow-throated American wood warbler	small bright-colored American songbird with a weak unmusical song
	European woodland warbler with dull yellow plumage