bang has 38 distinct synonyms spread across 10 of its 12 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.
to produce a sharp often metallic explosive or percussive sound
“One of them banged the sash of the window nearest my bed”
have sexual intercourse with
“This student sleeps with everyone in her dorm”
a sudden very loud noise
Synonyms, antonyms and the broader and narrower relations for bang come from Princeton University’s WordNet. Full sources and licences.