tes·ti·fy | \ˈte-stə-ˌfī \
testified; testifying

Definition of testify 

intransitive verb

1 : to make a solemn declaration under oath for the purpose of establishing a fact (as in a court)

2a : to make a statement based on personal knowledge or belief : bear witness

b : to serve as evidence or proof

3 : to express a personal conviction

transitive verb

1a : to bear witness to : attest

b : to serve as evidence of : prove

2 : to declare under oath before a tribunal or officially constituted public body

3 archaic

a : to make known (a personal conviction)

b : to give evidence of : show

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Other Words from testify

testifier \ˈte-stə-ˌfī(-ə)r \ noun

Synonyms for testify


attest, depose, swear, witness

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Examples of testify in a Sentence

She refused to testify about who had given her the information. She testified before Congress today. He agreed to testify against his drug dealer. He testified that he'd seen two people leave the building on the night of the murder. These statistics testify that the program is working. Several people testified during the revival meeting.
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Recent Examples on the Web

Jag invited us to the Algarve region of Portugal, where Sue Mead, a champion off-road racer, was on hand to testify. Bradley Berman, Popular Mechanics, "The Jaguar I-PACE and the Juiced-Up Future of Going Off-Road," 25 June 2018 But fear wants to keep us from telling our stories and testifying to truth. Alissa Wilkinson, Vox, "What two fictional Gileads can teach us about America in 2018," 12 July 2018 No one needed to testify to his bravery, though all did. Mike Newall, Philly.com, "Krasner didn't have to let down the dead officer's family | Mike Newall," 25 June 2018 Its experts have testified against the re-licensing of the Indian Point nuclear power plant on the Hudson. Billboard, "Aboard the Clearwater: Five Decades of Environmental Activism Rooted In Music," 13 June 2018 These results all testify to the persistent power of place, and not just social and racial characteristics, in shaping political attitudes. Ronald Brownstein, CNN, "Republicans and Democrats increasingly really do occupy different worlds," 12 June 2018 To Osteen, the Night of Hope crowds testify to the overwhelming success of his church's media-savvy evangelism. Katherine Blunt, Houston Chronicle, "Behind-the-scenes at a Joel Osteen 'Night of Hope' event: Books, bargains and stuff," 7 June 2018 The calls streamed in from small towns and major markets alike, testifying to the small town and rural importance of the medium. Thr Staff, The Hollywood Reporter, "1980: CNN Launches, Ted Turner Says It Won't Bow to Ad Pressure," 1 June 2018 Mark Zuckerberg has been testifying to the European Parliament via livestream, taking hard questions from reporters, and giving tech support to the Senate. Nicholas Thompson, WIRED, "Exclusive: Facebook Opens Up About False News," 23 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'testify.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of testify

14th century, in the meaning defined at intransitive sense 2a

History and Etymology for testify

Middle English testifien, from Anglo-French testifier, from Latin testificari, from testis witness

Latin testificari, from testis witness

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Phrases Related to testify

testify for the defense/prosecution

Statistics for testify

Last Updated

14 Oct 2018

Look-up Popularity

Time Traveler for testify

The first known use of testify was in the 14th century

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English Language Learners Definition of testify

: to talk and answer questions about something especially in a court of law while formally promising that what you are saying is true

: to talk about or say (something) in an honest and confident way

: to show that something is true or real : to give proof of something


tes·ti·fy | \ˈte-stə-ˌfī \
testified; testifying

Kids Definition of testify

: to make a formal statement of something sworn to be true Two witnesses testified in court.


tes·ti·fy | \ˈtes-tə-ˌfī \
testified; testifying

Legal Definition of testify 

intransitive verb

: to make a solemn declaration under oath or affirmation for the purpose of establishing a fact : give testimony

transitive verb

: to declare in testimony

Other Words from testify

testifier noun

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Comments on testify

What made you want to look up testify? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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