| Word | Definitions | Synonyms |
|---|---|---|
| rhea | (noun) larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia | Synonyms: Rhea americana |
| (noun) smaller of two tall fast-running flightless birds similar to ostriches but three-toed; found from Peru to Strait of Magellan | Synonyms: nandu, Pterocnemia pennata |