testify

American  

[tes-tuh-fahy] / ˈtɛs təˌfaɪ /

verb (used without object)

testifies, present (3rd person singular) testified, past participle, past testifying present participle

1. to bear witness; give or afford evidence.

2. Law. to give testimony under oath or solemn affirmation, usually in court.

3. to make solemn declaration.

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verb (used with object)

testifies, present (3rd person singular) testified, past participle, past testifying present participle

1. to bear witness to; affirm as fact or truth; attest.

2. to give or afford evidence of in any manner.

   Synonyms:

   prove, signify, show, indicate

3. Law. to state or declare under oath or affirmation, usually in court.

4. to declare, profess, or acknowledge openly.

testify British  

/ ˈtɛstɪˌfaɪ /

verb

1. (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

2. law to declare or give (evidence) under oath, esp in court

3. to be evidence (of); serve as witness (to)

   the money testified to his good faith

4. (tr) to declare or acknowledge openly

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Other Word Forms

Derived Forms

• testifier
  noun
• testification
  noun
• pretestify
  verb (used with object)
• retestify
  verb
• untestifying
  adjective

Conjugated Forms

Present

• have testified
  perfect
• has testified
  perfect 3rd person singular
• has been testifying
  perfect progressive 3rd person singular
• have been testifying
  perfect progressive
• am testifying
  progressive 1st person singular
• is testifying
  progressive 3rd person singular
• are testifying
  progressive
• testifying
  participle
• testifies
  singular 3rd person

Past

• had testified
  perfect
• were testifying
  progressive plural
• had been testifying
  perfect progressive
• was testifying
  progressive singular
• testified
  participle
• testified
  simple

Future

• will testify
  simple
• will have testified
  perfect
• will have been testifying
  perfect progressive
• will be testifying
  progressive

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.

Example Sentences

Because of Tom Jr's sudden guilty plea, Kow Mensah and two other Ghanian men – Gershon Norvivor and Kojo Attah – did not get the opportunity to testify.

From BBC • Jun. 8, 2026

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

From Slate • Jun. 8, 2026

Family members, including her granddaughter Naomi, were brought to testify.

From The Wall Street Journal • Jun. 1, 2026

He has been summoned to testify on June 2, and police have searched his offices and three unnamed companies, Spain's top criminal court said in a statement.

From Barron's • May 19, 2026

More significantly, Ikner testified that he'd been asked by Pearson, the trial prosecutor, to testify that Morrison's body had been dragged through the store from the front counter to the spot where it was found.

From "Just Mercy" by Bryan Stevenson

Related Words

• announce
• argue
• assert
• declare
• depose
• indicate
• swear