To attest means to declare or confirm that something is true, often formally or officially. When you attest to something, you're saying “Yes, I can confirm this is real” or “I personally know this is true.”

A doctor might attest that you were genuinely sick and missed school. A witness in court attests to what they saw happen. Your teacher might attest to your good character when writing a recommendation letter, confirming from their own experience that you're responsible and hardworking.

The word carries weight because it suggests personal knowledge or authority. You usually shouldn't attest to something you only heard about secondhand. When someone attests to a fact, they're putting their own credibility behind it, like saying “I stake my reputation on this being true.”

Documents sometimes need someone to attest to their authenticity by signing them, confirming they're genuine. Historical records that attest to an event provide evidence it really happened. The word attestation refers to the act of attesting or to a document that proves something is verified. When multiple sources attest to the same thing, it strengthens confidence that it's accurate.