invariance has 2 distinct synonyms spread across 1 of its 2 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 quality of being resistant to variation
the nature of a quantity or property or function that remains unchanged when a given transformation is applied to it
“the invariance of the configuration under translation”
Synonyms, antonyms and the broader and narrower relations for invariance come from Princeton University’s WordNet. Full sources and licences.