Synonyms for Rhea (same or very similar meaning)
WordNet sense 1 (smaller of two tall fast-running flightless birds similar to ostriches but three-toed; found from Peru to Strait of Magellan):
nandu, Pterocnemia pennataWordNet sense 2 (larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia):
Rhea americanaFrom the ODE community, based on WordNetadd/edit