blackcap vs true warbler

blackcap and true warbler both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackcap	Yes	No	No	No
true warbler	Yes	No	No	No

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

Other hypernyms of blackcap include Old World warbler.

blackcap (noun)	true warbler (noun)
small brownish-grey warbler with a black crown	small active brownish or greyish Old World birds
chickadee having a dark crown
small black-headed European gull
raspberry native to eastern North America having black thimble-shaped fruit