bat has 11 distinct synonyms spread across 6 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.
nocturnal mouselike mammal with forelimbs modified to form membranous wings and anatomical adaptations for echolocation by which they navigate
a small racket with a long handle used for playing squash
the club used in playing cricket
“a cricket bat has a narrow handle and a broad flat end for hitting”
a club used for hitting a ball in various games
strike with, or as if with a baseball bat
“bat the ball”
Synonyms, antonyms and the broader and narrower relations for bat come from Princeton University’s WordNet. Full sources and licences.
have a turn at bat
“Jones bats first, followed by Martinez”