rhea has 3 distinct synonyms spread across 2 of its 3 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
smaller of two tall fast-running flightless birds similar to ostriches but three-toed; found from Peru to Strait of Magellan
Synonyms, antonyms and the broader and narrower relations for rhea come from Princeton University’s WordNet. Full sources and licences.
larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia