authenticate

verb

au·​then·​ti·​cate ə-ˈthen-ti-ˌkāt 

ȯ-

authenticated; authenticating

transitive verb

: to prove or serve to prove to be real, true, or genuine

authenticate a document

authenticator

ə-ˈthen-ti-ˌkā-tər 

ȯ-

noun

Synonyms of authenticate

• certify
• guarantee
• affirm
• attest
• testify (to)

Choose the Right Synonym for authenticate

confirm, corroborate, substantiate, verify, authenticate, validate mean to attest to the truth or validity of something.

confirm implies the removing of doubts by an authoritative statement or indisputable fact.

confirmed the reports

corroborate suggests the strengthening of what is already partly established.

witnesses corroborated his story

substantiate implies the offering of evidence that sustains the contention.

the claims have yet to be substantiated

verify implies the establishing of correspondence of actual facts or details with those proposed or guessed at.

all statements of fact in the article have been verified

authenticate implies establishing genuineness by adducing legal or official documents or expert opinion.

handwriting experts authenticated the diaries

validate implies establishing validity by authoritative affirmation or by factual proof.

validated the hypothesis by experiments

Examples of authenticate in a Sentence

The signature has been authenticated.

a jeweler authenticated the diamond as real

Recent Examples on the Web

These 2 authenticated and graded Pokemon cards were stolen from the Nashcards store in Trappe, Pennsylvania, according to police. —Joe Brandt, CBS News, 12 May 2026

Gold coins can be a good fit for those who want to be able to easily liquidate their gold into currency, as bullion can require more work to authenticate and verify. —Liz Knueven, CNBC, 12 May 2026

That is because players making their first appearance at the tournament will wear the unique badge, which will later be authenticated, signed and eventually added to a packet of trading cards. —Greg O'Keeffe, New York Times, 9 May 2026

The timeline, whose origins are unclear, said Barket had authenticated the note as of January 2020. —Rachel Treisman, NPR, 7 May 2026

Word History

Etymology

borrowed from Medieval Latin authenticātus, past participle of authenticāre "to stamp as genuine or authoritative," derivative of Latin authenticus "original (of documents)" — more at authentic

Note: Compare as a secondary source Middle French autentiquer "to guarantee that something conforms to a norm."

First Known Use

1613, in the meaning defined above

Rhymes for authenticate

• abbreviate
• accelerate
• accommodate
• accumulate
• acuminate
• adjudicate
• adulterate
• affiliate
• agglomerate
• agglutinate
• alleviate
• amalgamate

Kids Definition

authenticate

verb

au·​then·​ti·​cate ə-ˈthent-i-ˌkāt 

ȯ-

authenticated; authenticating

: to prove or serve to prove that something is authentic

authentication

-ˌthent-i-ˈkā-shən 

noun

Legal Definition

authenticate

transitive verb

au·​then·​ti·​cate

authenticated; authenticating

1

: to prove or serve to prove that (something) is genuine

especially : to prove that (an item of evidence) is genuine for the purpose of establishing admissibility

2

: to make (a written instrument) valid and effective by marking especially with one's signature

authenticate a check