[v] 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"
[v] declare legally insane
[v] guarantee payment on; of checks
[v] authorize officially
[v] guarantee as meeting a certain standard; "certified grade AAA meat"