attest

verb

at·​test ə-ˈtest 

attested; attesting; attests

transitive verb

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

a word that was first attested in the 18th century

3

: to be proof of : manifest

Her record attests her integrity.

4

: to put on oath

intransitive verb

: to show, prove, or state that something is true or real

—usually used with to

I can attest to the truth of his statement.

attest to a belief

attester

ə-ˈte-stər 

noun

Synonyms

• authenticate
• avouch
• certify
• testify (to)
• vouch (for)
• witness

Choose the Right Synonym for attest

certify, attest, witness, vouch mean to testify to the truth or genuineness of something.

certify usually applies to a written statement, especially one carrying a signature or seal.

certified that the candidate had met all requirements

attest applies to oral or written testimony usually from experts or witnesses.

attested to the authenticity of the document

witness applies to the subscribing of one's own name to a document as evidence of its genuineness.

witnessed the signing of the will

vouch applies to one who testifies as a competent authority or a reliable person.

willing to vouch for her integrity

Examples of attest in a Sentence

I can attest that what he has said is true.

The certificate attests the authenticity of the painting.

Recent Examples on the Web

And in the case of the art, one that took several episodes to resolve, as eagle-eyed viewers can attest. —Mark Peikert, IndieWire, 6 Feb. 2025

The petitioner has attested under penalty of perjury to the accuracy of its claims and has a substantial interest in enforcing its rights. —Ars Technica, 29 Jan. 2025

As his cousin said, and his siblings have attested, RFK Jr. vaccinated his own children. —New York Daily News Editorial Board, New York Daily News, 29 Jan. 2025

As anyone who’s watched an iota of sports programming over the past few years can attest, the betting business doesn’t traffic in subtlety. —Sean Gregory / Boston, TIME, 27 Jan. 2025

Word History

Etymology

Middle French attester, from Latin attestari, from ad- + testis witness — more at testament

First Known Use

circa 1500, in the meaning defined at transitive sense 1a

Kids Definition

attest

verb

at·​test ə-ˈtest 

1

: to affirm to be true

2

: to be proof of

the result attests the truth of that statement

attestation

ˌa-ˌtes-ˈtā-shən 

noun

attester

ə-ˈtes-tər 

noun

Legal Definition

attest

verb

at·​test ə-ˈtest 

transitive verb

: to bear witness to : affirm to be true or genuine

specifically : to authenticate (as a will) by signing as a witness

intransitive verb

: to bear witness : testify

—often used with to

attestation

ˌa-ˌtes-ˈtā-shən 

noun

Etymology

Latin attestari, from ad to + testari to call to witness, from testis witness