destabilise has 1 distinct synonym 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 2 recorded opposites are stabilize, stabilise.
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.
become unstable
“The economy destabilized rapidly”
make unstable
“Terrorism destabilized the government”
Synonyms, antonyms and the broader and narrower relations for destabilise come from Princeton University’s WordNet. Full sources and licences.