attest definition

1. provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes
• examples: His high fever attested to his illness
• examples: The buildings in Rome manifest a high level of architectural sophistication
• examples: This decision demonstrates his sense of fairness
2. authenticate, affirm to be true, genuine, or correct, as in an official capacity
• examples: I attest this signature
3. establish or verify the usage of
• examples: This word is not attested until 1993