(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")
(guarantee payment on; of checks)
(authorize officially; "I am licensed to practice law in this state")
(guarantee as meeting a certain standard; "certified grade AAA meat")
(declare legally insane)
(endorsed authoritatively as having met certain requirements; "a certified public accountant")
(fit to be certified as insane (and treated accordingly))
(holding appropriate documentation and officially on record as qualified to perform a specified function or practice a specified skill; "a registered pharmacist"; "a registered hospital")