Antonyms for the word "in-validates" include "validates," "approves," "sanctions," "upholds," and "endorse." When something is validated, it is deemed to be legitimate, true, or worthy of recognition. Approval is the act of giving consent or agreement, while sanctioning is the formal authorization or approval of something. Upholding is the act of supporting or confirming that something is valid, while endorsing is the act of publicly advocating for or supporting a particular cause or idea. These antonyms are particularly useful when dealing with legal or professional matters that require the verification and recognition of the validity of a claim or argument.