performance has 6 distinct synonyms spread across 3 of its 5 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 dramatic or musical entertainment
“they listened to ten different performances”
the act of presenting a play or a piece of music or other entertainment
“we congratulated him on his performance at the rehearsal”
the act of performing; of doing something successfully; using knowledge as distinguished from merely possessing it
“they criticised his performance as mayor”
any recognized accomplishment
“they admired his performance under stress”
process or manner of functioning or operating
“the power of its engine determines its operation”
Synonyms, antonyms and the broader and narrower relations for performance come from Princeton University’s WordNet. Full sources and licences.