boatbill vs heron

boatbill and heron both are nouns.

Word	Noun	Adjective	Verb	Adverb
boatbill	Yes	No	No	No
heron	Yes	No	No	No

As nouns, heron is a hypernym of boatbill; that is, heron is a word with a broader meaning than boatbill:

boatbill: tropical American heron related to night herons
heron: grey or white wading bird with long neck and long legs and (usually) long bill

boatbill (noun)	heron (noun)
tropical American heron related to night herons	grey or white wading bird with long neck and long legs and (usually) long bill