The definition of attest is to affirm something to be true or to authenticate.(verb)
An example of attest is to prove to a college what an excellent candidate a student is for the school.
See attest in Webster's New World College Dictionary
Origin: Fr attester < L attestari < ad-, to + testari, to bear witness < testis, a witness: see testify
See attest in American Heritage Dictionary 4
verb at·test·ed, at·test·ing, at·tests verb, transitive
Origin: Latin attestārī
Origin: : ad-, ad-
Origin: + testārī, to be witness (from testis, witness; see trei- in Indo-European roots).
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