certify
Americanverb (used with object)
-
certifies,
present (3rd person singular)
-
certified,
past participle, past
-
certifying
present participle
-
to attest as certain; give reliable information of; confirm.
He certified the truth of his claim.
- Synonyms:
- guarantee, validate, verify, corroborate
-
to testify to or vouch for in writing.
The medical examiner will certify his findings to the court.
-
to guarantee; endorse reliably.
to certify a document with an official seal.
-
to guarantee (a check) by writing on its face that the account against which it is drawn has sufficient funds to pay it.
-
to award a certificate to (a person) attesting to the completion of a course of study or the passing of a qualifying examination.
-
to declare legally insane and committable to a mental institution.
-
Archaic. to assure or inform with certainty.
verb (used without object)
-
certifies,
present (3rd person singular)
-
certified,
past participle, past
-
certifying
present participle
verb
-
to confirm or attest (to), usually in writing
the letter certified her age
-
(tr) to endorse or guarantee (that certain required standards have been met)
-
to give reliable information or assurances
he certified that it was Walter's handwriting
-
(tr) to declare legally insane
-
(tr) (of a bank) to state in writing on (a cheque) that payment is guaranteed
Other Word Forms
Derived Forms
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certifiernoun
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precertifyverb (used with object)
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recertifyverb (used with object)
-
uncertifyingadjective
Inflected Forms
Participles
Conjugated Forms
Present
-
certifysimple
-
certifiessimple
-
have certifiedperfect
-
has certifiedperfect
-
am certifyingprogressive
-
are certifyingprogressive
-
is certifyingprogressive
-
have been certifyingperfect progressive
-
has been certifyingperfect progressive
Past
-
certifiedsimple
-
had certifiedperfect
-
was certifyingprogressive
-
were certifyingprogressive
-
had been certifyingperfect progressive
Future
Etymology
Origin of certify
1300–50; Middle English certifien < Middle French certifier < Late Latin certificāre, equivalent to Latin certi- (combining form of certus decided; see certain) + -ficāre -fy
Explanation
To certify is to provide proof for something or to license someone, like a lawyer. You can certify a lawyer or certify that someone’s insane. Either way, when you certify something, you make it official. To certify is to have evidence that something is true, to make certain. If you certify that you own a house, you prove it's yours. Vouching for a friend can certify that the friend is a good person. Professionals like lawyers, doctors, and accountants must be certified. Being certified assures others that the person is qualified. Certify also refers to declaring someone legally insane, so make sure your doctor is certified by the medical board, not the loony bin.
Vocabulary lists containing certify
Stargirl
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The Dawes Act
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This Week In Words: November 28–December 4, 2020
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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.
See Examples For:
The National Highway Traffic Safety Administration said it opened an audit query to examine the process and technical data Tesla used to certify the Cybercab.
From Los Angeles Times ● Sep. 4, 2026
Spirit said it is “engaging a third party to deidentify the data and certify that the data sold at auction is compliant with applicable privacy laws and regulations.”
From The Wall Street Journal ● Aug. 19, 2026
March 8: US regulators with the Federal Aviation Administration certify the 737 MAX 8, which takes its first commercial flight weeks later.
From Barron's ● Aug. 3, 2026
People can now certify their expertise with particular AI platforms and strategies through paid and free certification programs.
From MarketWatch ● Jul. 31, 2026
“Well, then, it’s up to me to certify you, isn’t it?”
From "Challenger Deep" by Neal Shusterman
Most other closed-loop systems ran at about 32C in 2024, according to the Uptime Institute, which certifies data centers.
From Barron's ● Sep. 7, 2026
Denise Brown, whose Caregiving Years Training Academy certifies caregiving consultants, says Nonie’s monthlong stay demonstrated her desire to make sure her parents were all right.
From The Wall Street Journal ● Jul. 4, 2026
The form will be given to you two days prior to the day your county certifies the election, so be sure to fill it out and return it to your county elections office right away.
From Los Angeles Times ● Jun. 2, 2026
"It's going to give clarity to the UK market, installers, builders, manufacturers, that there's a significant market that's there," said Garry Felgate, CEO of MCS Foundation, which certifies installers of low carbon heating systems.
From BBC ● Mar. 23, 2026
That word certifies to the savagery of primitive man.
From The Works of Robert G. Ingersoll, Vol. 4 (of 12) Dresden Edition?Lectures by Robert Green Ingersoll
The key to family harmony with either of these approaches is to maintain the person’s dignity as much as possible, said Kate Nattoli, a certified dementia practitioner with Crescent Grove Advisors.
From MarketWatch ● Oct. 6, 2026
Ozuna said that her daughter, the kindergarten teacher, holds a college degree and is working toward becoming a certified teacher but has struggled to get through a series of financial hoops.
From Salon ● Oct. 1, 2026
The FAA certified the smaller, long-delayed 737 MAX 7 on August 3.
From Barron's ● Sep. 28, 2026
One of the bills, introduced by Stefani, expands the ability of certified nurse-midwives to provide care for pregnant and postpartum patients by specifying that supervision by a physician is not required when providing certain services.
From Los Angeles Times ● Sep. 27, 2026
We certainly would not have certified a Viking landing site as safe if orbital photographs had shown such shifting patterns.
From "Cosmos" by Carl Sagan
Removing the pilot would have added the cost and complication of certifying a robot jet to fly fast over urban areas.
From BBC ● Sep. 24, 2026
Along with more money for counties and expanded voter education efforts, Romero suggested steps to shorten the California timeline for certifying results.
From Salon ● Jun. 9, 2026
The certifying official notes that the filer “will be in compliance” only “once the filer divests these assets.”
From MarketWatch ● May 7, 2026
The Federal Aviation Administration is responsible for certifying civil aircraft in the U.S., including planes used for commercial flights.
From The Wall Street Journal ● Jan. 30, 2026
Then a county judge issued a five-day restraining order forbidding the governor from certifying the result.
From "Votes for Women!" by Winifred Conkling
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
