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

The couple has neither confirmed nor denied the happy event, but the tabloid did post pictures of Gaga carrying an infant in a sling on September 11. — Bethy Squires, Vulture, 12 Sep. 2026

Before presenting an update or accepting another task, confirm what success looks like and how progress should be reported. — Tarot.com, Sun Sentinel, 12 Sep. 2026

Jani said that the study did not analyze individual-level data on alcohol consumption or confirm a reason for why alcohol-attributable cancer deaths increased. — Arkansas Online, 12 Sep. 2026

Start with the task that will make the clearest difference, then confirm what success looks like before spending hours on details nobody requested. — Tarot.com, Chicago Tribune, 11 Sep. 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
• budworm
• cutworm
• earthworm
• infirm
• midterm
• ringworm
• tapeworm
• wireworm
• angiosperm
• echinoderm

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