gallinaceous bird vs gallinacean

gallinaceous bird and gallinacean both are nouns.

Word	Noun	Adjective	Verb	Adverb
gallinaceous bird	Yes	No	No	No
gallinacean	Yes	No	No	No

As nouns, gallinaceous bird and gallinacean are synonyms defined as:

gallinaceous bird and gallinacean: heavy-bodied largely ground-feeding domestic or game birds

gallinaceous bird (noun)	gallinacean (noun)
heavy-bodied largely ground-feeding domestic or game birds	heavy-bodied largely ground-feeding domestic or game birds