bypass has 8 distinct synonyms spread across 3 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 surgically created shunt (usually around a damaged part)
a conductor having low resistance in parallel with another device to divert a fraction of the current
avoid something unpleasant or laborious
“You cannot bypass these rules!”
Synonyms, antonyms and the broader and narrower relations for bypass come from Princeton University’s WordNet. Full sources and licences.