CERTIFY Synonyms: 100 Similar and Opposite Words

Q: How does the verb 'certify' contrast with its synonyms?

Some common synonyms of certify are attest , vouch , and witness . While all these words 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

Q: When would 'attest' be a good substitute for 'certify'?

The meanings of attest and certify largely overlap; however, attest applies to oral or written testimony usually from experts or witnesses. // attested to the authenticity of the document

Q: In what contexts can 'vouch' take the place of 'certify'?

In some situations, the words vouch and certify are roughly equivalent. However, vouch applies to one who testifies as a competent authority or a reliable person. // willing to vouch for her integrity

Q: When could 'witness' be used to replace 'certify'?

Although the words witness and certify have much in common, witness applies to the subscribing of one's own name to a document as evidence of its genuineness. // witnessed the signing of the will

certify

verb

ˈsər-tə-ˌfī

Definition of certify next

as in to guarantee

to declare (something) to be true or genuine experts certified the letter as indeed having been written by Abraham Lincoln

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as in to enable

to give official or legal power to certified her as a teacher

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Antonyms & Near Antonyms

as in to verify

to give evidence or testimony to the truth or factualness of please bring in a doctor's note to certify that you were really sick

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Antonyms & Near Antonyms

Synonym Chooser

How does the verb certify contrast with its synonyms?

Some common synonyms of certify are attest, vouch, and witness. While all these words 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

When would attest be a good substitute for certify?

The meanings of attest and certify largely overlap; however, attest applies to oral or written testimony usually from experts or witnesses.

attested to the authenticity of the document

In what contexts can vouch take the place of certify?

In some situations, the words vouch and certify are roughly equivalent. However, vouch applies to one who testifies as a competent authority or a reliable person.

willing to vouch for her integrity

When could witness be used to replace certify?

Although the words witness and certify have much in common, witness applies to the subscribing of one's own name to a document as evidence of its genuineness.

witnessed the signing of the will

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of certify The University of Central Florida is expected to be certified by the Board of Governors as a preeminent state research university later this year. —

Cbs Miami Team, CBS News, 11 Feb. 2026 Some schools don’t have many teachers who are certified for dual credit, for example. —

Theo Peck-Suzuki, Hartford Courant, 11 Feb. 2026 Starting in the 1970s, states like Oregon and California, where organic farming was taking off, responded by passing regulations that would allow products to be certified as organic. —

Annie Levin, Washington Post, 10 Feb. 2026 Democrat Joe Biden won Georgia by about 11,800 votes in an election overseen by a Republican secretary of state and certified by a Republican governor. —

Kate Brumback, Chicago Tribune, 10 Feb. 2026 See All Example Sentences for certify

Recent Examples of Synonyms for certify

Verb

Whether Republicans and Democrats would be willing to pass another short-term DHS funding extension to buy time for a compromise isn't guaranteed, either.

— Zachary Schermele, USA Today, 10 Feb. 2026
Dalton is guaranteed $2 million in 2026, but Morgan has openly discussed his desire to add a younger, developmental quarterback to the mix behind Young.

— Mike Kaye February 10, Charlotte Observer, 10 Feb. 2026

Definition of guarantee

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certifies

certify

certifying

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“Certify.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/certify. Accessed 16 Feb. 2026.

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Last Updated: 15 Feb 2026 - Updated example sentences

Synonyms of certify

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