quash

verb

To forcefully suppress or put an end to something, often a rebellion or rumour.

"The government worked to quash the uprising."

verb

To officially reject or make void, especially a legal decision or ruling.

"The High Court moved to quash the earlier verdict."

Thesaurus

Synonyms: avoid, nullify, void, annul, invalidate, keep down, subdue, repress, subjugate, reduce

Antonyms: formalise, formalize, validate