exposition has 3 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.
a systematic interpretation or explanation (usually written) of a specific topic
a collection of things (goods or works of art etc.) for public display
an account that sets forth the meaning or intent of a writing or discourse
“we would have understood the play better if there had been some initial exposition of the background”
(music) the section of a movement (especially in sonata form) where the major musical themes first occur
Synonyms, antonyms and the broader and narrower relations for exposition come from Princeton University’s WordNet. Full sources and licences.