Synonyms

affirm

American

[uh-furm] / əˈfɜrm /

verb (used with object)

to state or assert positively; maintain as true.

to affirm one's loyalty to one's country; He affirmed that all was well.

Synonyms:

testify, depose, asseverate, aver

Antonyms:

deny
to confirm or ratify.

The appellate court affirmed the judgment of the lower court.

Synonyms:

endorse, approve
to assert solemnly.

He affirmed his innocence.
to express agreement with or commitment to; uphold; support.

to affirm human rights.
to support (someone) by giving approval, recognition, or encouragement.

She described the unhappy memory of her father, who had neither disciplined nor affirmed her.

verb (used without object)

Law.
1. to state something solemnly before a court or magistrate, but without oath.
2. to ratify and accept a voidable transaction.
3. (of an appellate court) to determine that the action of the lower court shall stand.

affirm British

/ əˈfɜːm /

verb

(may take a clause as object) to declare to be true; assert positively
to uphold, confirm, or ratify
(intr) law to make an affirmation

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See declare.

Other Word Forms

Derived Forms

Conjugated Forms

Present

Past

Future

Etymology

Origin of affirm

First recorded in 1300–50; from Latin affirmāre, equivalent to af- af- + firmāre “to make firm” ( see firm ¹); replacing Middle English a(f)fermen, from Middle French afermer, from Latin

Explanation

To affirm something is to give it a big "YES" or to confirm that it is true. The verb affirm means to answer positively, but it has a more weighty meaning in legal circles. People are asked to swear an oath or affirm that they will tell the truth in a court of law. Lawyers may ask people to affirm facts, and judges may affirm rulings. In these cases, affirm means to verify or attest to the validity of something.

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Vocabulary lists containing affirm

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Affirm in your heart and in your mind that love itself is an infinite resource.

From Los Angeles Times • May 8, 2026

Affirm last year signed forward-flow agreements for roughly up to $9.75 billion from Liberty Mutual Investments, the investment firm of Liberty Mutual; PGIM, the asset-management business of Prudential Financial; and New York Life.

From The Wall Street Journal • Apr. 19, 2026

Morgan Stanley expects Affirm to introduce an earnings-per-share target of $2.50 to $3 for fiscal 2028, which would be above the consensus forecast of $2.42.

From Barron's • Apr. 17, 2026

Deposits are held by Cross River Bank, which has made a name for itself by partnering with fintech companies like Affirm.

From MarketWatch • Apr. 16, 2026

"Affirm, Flight. Intermittent signal from the ship, but no probe."

From "The Martian" by Andy Weir

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023