Definition of ATTEST

to declare (something) to be true or genuine <the appraiser attests that the lamp is indeed an original Tiffany>
Synonyms attest, authenticate, avouch, testify (to), vouch (for), witness
to make a solemn declaration under oath for the purpose of establishing a fact <an eyewitness who will attest to my innocence>
Related Words verify; vouch; promise, vow
to give evidence or testimony to the truth or factualness of <I'll attest that she was at the party>
Related Words avouch, back (up), testify (to), vouch (for), witness; guarantee, warrant; affirm, assert, aver, avow, declare, profess; demonstrate, document, establish, prove, reinforce (also reenforce)
Antonyms disprove, rebut, refute

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