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verb cer·ti·fy \ˈsər-tə-ˌfī\

Simple Definition of certify

  • : to say officially that something is true, correct, or genuine

  • : to say officially that something or someone has met certain standards or requirements

  • : to say officially that someone is insane and in need of treatment

Source: Merriam-Webster's Learner's Dictionary

Full Definition of certify



  1. transitive verb
  2. 1 :  to attest authoritatively: as a :  confirm b :  to present in formal communication c :  to attest as being true or as represented or as meeting a standard d :  to attest officially to the insanity of

  3. 2 :  to inform with certainty :  assure

  4. 3 :  to guarantee (a personal check) as to signature and amount by so indicating on the face

  5. 4 :  to recognize as having met special qualifications (as of a governmental agency or professional board) within a field <agencies that certify teachers>


play \-ˌfī(-ə)r\ noun

Examples of certify in a sentence

  1. A judge must certify the contract.

  2. The document has been certified by the court.

  3. The car dealer certifies each car before it is sold.

  4. Has your doctor been certified?

Origin and Etymology of certify

Middle English certifien, from Anglo-French certefier, from Late Latin certificare, from Latin certus certain — more at certain

First Known Use: 14th century

Synonym Discussion of certify

certify, attest, witness, vouch mean to testify to the truth or genuineness of something. certify usually applies to a written statement, especially one carrying a signature or seal <certified that the candidate had met all requirements>. attest applies to oral or written testimony usually from experts or witnesses <attested to the authenticity of the document>. witness applies to the subscribing of one's own name to a document as evidence of its genuineness <witnessed the signing of the will>. vouch applies to one who testifies as a competent authority or a reliable person <willing to vouch for her integrity>.

synonyms see in addition approve

Rhymes with certify

abide by, Adonai, alibi, alkali, amplify, apple-pie, argufy, assegai, azo dye, basify, beautify, butterfly, by-and-by, caddis fly, calcify, 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, testify, 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

CERTIFY Defined for Kids


verb cer·ti·fy \ˈsər-tə-ˌfī\

Definition of certify for Students



  1. 1 :  to show to be true or as claimed by a formal or official statement <Only the teacher can certify test scores.>

  2. 2 :  to guarantee the quality, fitness, or value of officially <certified milk> <certify a check>

  3. 3 :  to show to have met certain requirements <His school needs to certify him for graduation.>

Medical Dictionary


verb cer·ti·fy \ˈsərt-ə-ˌfī\

Medical Definition of certify




  1. 1

  2. transitive verb

  3. :  to attest authoritatively; especially :  to attest officially to the mental illness of

  4. 2:  to designate as having met the requirements to practice medicine or a particular medical specialty

  5. intransitive verb

  6. :  to attest by a certificate <five year program leading to examination by the American Board which certifies in that specialty—Bulletin of Meharry Medical College>


\ˈsər-tə-ˌfī-ə-bəl, ˌsər-tə-ˈfī-\ adjective


\-blē\play adverb

Law Dictionary


transitive verb cer·ti·fy \ˈsər-tə-ˌfī\

Legal Definition of certify



  1. 1 :  to state authoritatively: as a :  to give assurance of the validity of <certify corporate records> b :  to present in formal communication (as an order) especially for review by an appellate court <the court may certify the question to the Supreme Judicial Court — R. T. Gerwatowski> — see also certification c :  to state as being true or as reported or as meeting a standard <refused to certify the suit as a class action and dismissed it — Marcia Coyle>

  2. 2 :  to guarantee (a personal check) as to signature and amount by so indicating (as by stamping certified) on the face — see also certified check at check

  3. 3a :  certificate, license b :  to designate (a labor union) as an exclusive bargaining agent or representative

Origin and Etymology of certify

Medieval Latin certificare, from Late Latin, to assure, convince, from Latin certus certain + -ficare to make

Seen and Heard

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


to criticize in a loud and angry way

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