confirm

verb

con·​firm kən-ˈfərm 

confirmed; confirming; confirms

transitive verb

1

: to give approval to : ratify

confirm a treaty

2

: to give new assurance of the validity of : remove doubt about by authoritative act or indisputable fact

confirm a rumor

confirm an order

3

: to make firm or firmer : strengthen

confirm one's resolve

4

: to administer the rite of confirmation to

confirmability

kən-ˌfər-mə-ˈbi-lə-tē 

noun

confirmable

kən-ˈfər-mə-bəl 

adjective

Synonyms of confirm

• verify
• argue

Choose the Right Synonym for confirm

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 confirm in a Sentence

The tests confirmed the doctors' suspicions of cancer.

The attack confirmed her worst fears about the neighborhood.

The award confirmed her status as one of the great movie actresses.

The dentist's office called to confirm your appointment for tomorrow.

We have a reservation for you for tomorrow night. Please call to confirm.

Recent Examples on the Web

Kathy Svitil, a spokesperson for the California Institute of Technology, confirmed a record of an undergraduate student by the name of Cole Allen who graduated in 2017, but declined to release more information. —Michael Collins, USA Today, 27 Apr. 2026

Tottenham confirmed the injury in post on social media on Monday. —Dan Kilpatrick, New York Times, 27 Apr. 2026

Holmes confirmed that the Lions have canceled their annual rookie minicamp, a departure from the post-draft schedule followed by most NFL teams. —Bob Tripi, Chicago Tribune, 26 Apr. 2026

Future observations, especially across more wavelengths and with next-generation detectors, will be crucial to confirm whether this behavior is typical or a rare exception. —Rupendra Brahambhatt, Interesting Engineering, 26 Apr. 2026

Word History

Etymology

Middle English, from Anglo-French cunfermer, from Latin confirmare, from com- + firmare to make firm, from firmus firm

First Known Use

13th century, in the meaning defined at sense 1

Rhymes for confirm

• affirm
• bookworm
• cutworm
• earthworm
• infirm
• midterm
• tapeworm
• wireworm
• angiosperm
• echinoderm
• berm
• ferm

Kids Definition

confirm

verb

con·​firm kən-ˈfərm 

1

: to make firm or firmer (as in habit, faith, or intention) : strengthen

2

: approve sense 2, ratify

confirm a treaty

3

: to administer confirmation to

4

: to make sure of the truth of : verify

confirm a suspicion

confirmable

-ˈfər-mə-bəl 

adjective

Legal Definition

confirm

transitive verb

con·​firm

1

a

: to make valid by necessary formal approval

the debtor's chapter 13 plan confirmed by the court

b

: to vote approval of

confirm a nomination

2

: to give formal acknowledgment of receipt of

3

: to remove doubt about by authoritative act or indisputable fact

a consent decree confirming Capt. Brown's right to his cargo

—W. G. Young