ratite vs flightless bird

ratite and flightless bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
ratite	Yes	No	No	No
flightless bird	Yes	No	No	No

As nouns, ratite and flightless bird are synonyms defined as:

ratite and flightless bird: flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds

Other synonyms of ratite include ratite bird.

ratite (noun)	flightless bird (noun)
flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds	flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds