The verb ratify is to approve in writing or to set rules such as contracts, treaty or agreement, making it officially valid. It is usually done by signing or voting for it.

Synonyms are accredit, confirm, approve, or authorize.

The word origins from Middle English ratifien, Anglo-French (13th century) ratifier, Medieval Latin ratificare, meaning “confirm, approve” literally “fix by reckoning”. In Latin ratus meaning determined, approved, fixed by calculation or certain (past participle of reri which means to calculate).

It only took hours for the Mayor to ratify the executive order, stating that work and classes will be suspended because of the typhoon.

After her contract was ratified, she worked harder than ever.

I really don’t understand why the government hasn’t ratified this agreement yet.