certify
Americanverb (used with object)
-
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)
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
- certifier noun
- precertify verb (used with object)
- recertify verb (used with object)
- uncertifying adjective
Etymology
Origin of certify
1300–50; Middle English certifien < Middle French certifier < Late Latin certificāre, equivalent to Latin certi- (combining form of certus decided; certain ) + -ficāre -fy
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.
Boeing is working to certify the widebody jet for commercial service.
From Barron's • Feb. 19, 2026
Instead of going through the usual regulatory process, residents using federal emergency funds to rebuild would have to certify compliance with local standards.
From Los Angeles Times • Feb. 3, 2026
The company doesn’t generate significant sales yet as it works to certify its aircraft for commercial service.
From Barron's • Jan. 29, 2026
But charities have told BBC News employers will still be able to certify themselves without employing "a single disabled person".
From BBC • Jan. 15, 2026
“They will certify the results of this test before we make them public,” said Dr. Garcia.
From "The Smartest Kid in the Universe" by Chris Grabenstein
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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.