pigeon vs columbiform bird

pigeon and columbiform bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
pigeon	Yes	No	No	No
columbiform bird	Yes	No	No	No

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

pigeon: wild and domesticated birds having a heavy body and short legs
columbiform bird: a cosmopolitan order of land birds having small heads and short legs with four unwebbed toes

pigeon (noun)	columbiform bird (noun)
wild and domesticated birds having a heavy body and short legs	a cosmopolitan order of land birds having small heads and short legs with four unwebbed toes