rhea vs ratite

rhea and ratite both are nouns.

Word	Noun	Adjective	Verb	Adverb
rhea	Yes	No	No	No
ratite	Yes	No	No	No

As nouns, ratite is a hypernym of rhea; that is, ratite is a word with a broader meaning than rhea:

rhea: larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia
ratite: flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds

Other hypernyms of rhea include flightless bird, ratite bird.

As nouns, ratite is a hypernym of rhea; that is, ratite is a word with a broader meaning than rhea:

rhea: smaller of two tall fast-running flightless birds similar to ostriches but three-toed; found from Peru to Strait of Magellan
ratite: flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds

Other hypernyms of rhea include flightless bird, ratite bird.

rhea (noun)	ratite (noun)
larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia	flightless birds having flat breastbones lacking a keel for attachment of flight muscles: ostriches, cassowaries, emus, moas, rheas, kiwis, elephant birds
smaller of two tall fast-running flightless birds similar to ostriches but three-toed; found from Peru to Strait of Magellan