27 synonyms for mandate such as authority, bidding, acceptance, and approval. Mandate is a noun, and its antonyms are optional and voluntary.
Bidding, charge, command, commission, decree, direction, directive, edict, fiat, injunction, instruction, law, order, ordinance, pronunciamento, ruling, statute, ukase, and warrant.
Acceptance, approval, authority, authorization, endorsement, ratification, and sanction.