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verb tes·ti·fy \ˈtes-tə-ˌfī\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of testify



  1. intransitive verb
  2. 1a :  to make a statement based on personal knowledge or belief :  bear witnessb :  to serve as evidence or proof

  3. 2 :  to express a personal conviction

  4. 3 :  to make a solemn declaration under oath for the purpose of establishing a fact (as in a court)

  5. transitive verb
  6. 1a :  to bear witness to :  attestb :  to serve as evidence of :  prove

  7. 2 archaic a :  to make known (a personal conviction)b :  to give evidence of :  show

  8. 3 :  to declare under oath before a tribunal or officially constituted public body


play \-ˌfī(-ə)r\ noun

Examples of testify in a sentence

  1. She refused to testify about who had given her the information.

  2. She testified before Congress today.

  3. He agreed to testify against his drug dealer.

  4. He testified that he'd seen two people leave the building on the night of the murder.

  5. These statistics testify that the program is working.

  6. Several people testified during the revival meeting.

Origin and Etymology of testify

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

First Known Use: 14th century

Rhymes with testify

abide by, Adonai, alibi, alkali, amplify, apple-pie, argufy, assegai, azo dye, basify, beautify, butterfly, by-and-by, caddis fly, calcify, certify, Chou En-lai, citify, clarify, classify, coalify, cockneyfy, codify, college try, cottage pie, crucify, cut-and-try, cutie-pie, DIY, damnify, damselfly, dandify, deify, densify, dignify, dobsonfly, do-or-die, dragonfly, dulcify, eagle eye, edify, evil eye, falsify, fancify, fortify, frenchify, fructify, gasify, Gemini, gentrify, glorify, goggle-eye, goldeneye, gratify, Haggai, harvest fly, hexerei, high and dry, hip and thigh, Hokusai, hook and eye, horrify, hoverfly, humble pie, Iceni, justify, kiss good-bye, lazy eye, lignify, liquefy, lithify, Lorelei, lullaby, Madurai, magnify, Malachi, Maracay, minify, modify, mollify, Molokai, Mordecai, mortify, multi-ply, multiply, mummify, mystify, nazify, notify, nullify, occupy, old school tie, on standby, on the fly, ossify, overbuy, overfly, overlie, pacify, Paraguay, passerby, peccavi, petrify, PPI, preachify, prettify, private eye, prophesy, purify, putrefy, qualify, quantify, ramify, rarefy, ratify, RBI, rectify, reify, res gestae, robber fly, runner's high, Russify, samurai, sanctify, satisfy, scarify, schwarmerei, semidry, set store by, shepherd's pie, shoofly pie, signify, simplify, Spanish fly, specify, speechify, stratify, stultify, stupefy, sweetie pie, Tenebrae, terrify, tie-and-dye, tigereye, Trans Alai, tumble dry, typify, uglify, underlie, unify, Uruguay, Veneti, verify, versify, vilify, vinify, vitrify, vivify, weather eye, Windsor tie, xanthene dye, yuppify, zombify

TESTIFY Defined for Kids


verb tes·ti·fy \ˈte-stə-ˌfī\

Definition of testify for Students



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

Law Dictionary


verb tes·ti·fy \ˈtes-tə-ˌfī\

Legal Definition of testify



  1. intransitive verb
  2. :  to make a solemn declaration under oath or affirmation for the purpose of establishing a fact :  give testimony
  3. transitive verb
  4. :  to declare in testimony



Origin and Etymology of testify

Latin testificari, from testis witness

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to criticize in a loud and angry way

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