authenticate
v.v. to prove that something is real and not a fake. You use this when checking if a document, a painting, or a person is who or what they say they are.
v. to verify the authenticity of an object, document, or person. Transitive — requires a direct object to be verified.
The expert will authenticate the painting to see if it is real.
Before the bank processes the large withdrawal, they must authenticate the signature on the check against the customer's records.
Advanced forensic techniques allow investigators to authenticate digital evidence, ensuring that the data has not been altered or corrupted since its initial collection at the crime scene.
From Medieval Latin authenticō. By surface analysis, authentic + -ate (verb-forming suffix).
From authentic + -ate (adjective-forming suffix)