Synonyms

testify

American

[tes-tuh-fahy] / ˈtɛs təˌfaɪ /

verb (used without object)

to bear witness; give or afford evidence.
Law. to give testimony under oath or solemn affirmation, usually in court.
to make solemn declaration.

verb (used with object)

to bear witness to; affirm as fact or truth; attest.
to give or afford evidence of in any manner.

Synonyms:

prove, signify, show, indicate
Law. to state or declare under oath or affirmation, usually in court.
to declare, profess, or acknowledge openly.

testify British

/ ˈtɛstɪˌfaɪ /

verb

(when tr, may take a clause as object) to state (something) formally as a declaration of fact

I testify that I know nothing about him
law to declare or give (evidence) under oath, esp in court
to be evidence (of); serve as witness (to)

the money testified to his good faith
(tr) to declare or acknowledge openly

"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

Other Word Forms

Derived Forms

Conjugated Forms

Present

Past

Future

Etymology

Origin of testify

1350–1400; Middle English testifyen < Latin testificārī to bear witness, equivalent to testi ( s ) witness + -ficārī -fy

Explanation

To testify is to make a statement or provide evidence, usually in court. Witnesses testify for the prosecution or defense. If you've ever seen a TV show about lawyers, you've probably seen someone testifying: putting their hand on the Bible, sitting in the witness seat, and telling what they know about a case. Testifying is serious business, but it doesn't always happen in court: If someone knows you're good at math, they can testify to your math skills. Or if you've been to a restaurant, you can testify to your friends that it has awesome desserts.

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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.

Courts Director Robert Conrad will testify before an appropriations subcommittee this summer; members should question him about workplace conduct.

From Slate • Jun. 8, 2026

They are difficult because a language is being compelled to testify, and because a poet is asking who can bear witness.

From The Wall Street Journal • Jun. 5, 2026

Chantal wants to testify so others avoid her misfortune.

From Barron's • Jun. 5, 2026

The program allows non-citizens to testify before a grand jury to mitigate consequences of actual or pending charges against them or others.

From Los Angeles Times • Jun. 4, 2026

So Cowell went on to extend his definition of evidence: in a trial, he says, the accused is called on to testify.

From "The Invention of Science" by David Wootton

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