Simple Definition of attest
: to show, prove, or state that something is true or real
Full Definition of attest
1 a : to affirm to be true or genuine; specifically : to authenticate by signing as a witness b : to authenticate officially
2 : to establish or verify the usage of
3 : to be proof of : manifest <her record attests her integrity>
4 : to put on oath
: to bear witness : testify <attest to a belief>
Examples of attest
I can attest that what he has said is true.
The certificate attests the authenticity of the painting.
Origin of attest
Middle French attester, from Latin attestari, from ad- + testis witness — more at testament
First Known Use: circa 1500
Synonym Discussion of attest
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