Look up attest or attestation in Wiktionary, the free dictionary.

Attestation may refer to:

• Attestation clause, verification of a document
• Oath of Allegiance (United Kingdom)#Armed forces The date from which the service of a member of the armed forces begins is the date of attestation, on which the oath of allegiance is sworn (though the recruit might not report for training until a later date)
• Various police oaths in the United Kingdom
• The process of validating the integrity of a computing device such as a server needed for trusted computing
• Attested language
• Testimony