amazon has 2 distinct synonyms spread across 2 of its 4 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.
(Greek mythology) one of a nation of women warriors of Scythia (who burned off the right breast in order to use a bow and arrow more effectively)
a major South American river; arises in the Andes and flows eastward into the South Atlantic; the world's 2nd longest river (4000 miles)
mainly green tropical American parrots
Synonyms, antonyms and the broader and narrower relations for amazon come from Princeton University’s WordNet. Full sources and licences.