chestnut has 1 distinct synonym spread across 1 of its 7 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.
wood of any of various chestnut trees of the genus Castanea
any of several attractive deciduous trees yellow-brown in autumn; yield a hard wood and edible nuts in a prickly bur
1 of the 7 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for chestnut.
Synonyms, antonyms and the broader and narrower relations for chestnut come from Princeton University’s WordNet. Full sources and licences.
edible nut of any of various chestnut trees of the genus Castanea
a small horny callus on the inner surface of a horse's leg
a dark golden-brown or reddish-brown horse