transgression has 1 distinct synonym spread across 1 of its 3 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.
the act of transgressing; the violation of a law or a duty or moral principle
“the boy was punished for the transgressions of his father”
the spreading of the sea over land as evidenced by the deposition of marine strata over terrestrial strata
the action of going beyond or overstepping some boundary or limit
Synonyms, antonyms and the broader and narrower relations for transgression come from Princeton University’s WordNet. Full sources and licences.