cat has 33 distinct synonyms spread across 8 of its 10 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.
feline mammal usually having thick soft fur and no ability to roar: domestic cats; wildcats
the leaves of the shrub Catha edulis which are chewed like tobacco or used to make tea; has the effect of a euphoric stimulant
“in Yemen kat is used daily by 85% of adults”
a whip with nine knotted cords
“British sailors feared the cat”
a large tracked vehicle that is propelled by two endless metal belts; frequently used for moving earth in construction and farm work
a method of examining body organs by scanning them with X rays and using a computer to construct a series of cross-sectional scans along a single axis
Synonyms, antonyms and the broader and narrower relations for cat come from Princeton University’s WordNet. Full sources and licences.