devolution has 2 distinct synonyms spread across 2 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. Its one recorded opposite is evolution.
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 process of declining from a higher to a lower level of effective power or vitality or essential quality
Synonyms, antonyms and the broader and narrower relations for devolution come from Princeton University’s WordNet. Full sources and licences.
the delegation of authority (especially from a central to a regional government)