The verb certify has 5 senses (first 3 from tagged texts)
1. (4) attest, certify, manifest, demonstrate, evidence -- (provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes; "His high fever attested to his illness"; "The buildings in Rome manifest a high level of architectural sophistication"; "This decision demonstrates his sense of fairness")
2. (3) certify -- (guarantee payment on; of checks)
3. (2) license, licence, certify -- (authorize officially; "I am licensed to practice law in this state")
4. certify, endorse, indorse -- (guarantee as meeting a certain standard; "certified grade AAA meat")