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Showing results for certify. Search instead for uncertifi.
Definitions

certify

[sur-tuh-fahy] / ˈsɜr təˌfaɪ /
VERB
declare as true
Synonyms
STRONGEST
accredit approve ascertain authorize confirm endorse guarantee license notify validate verify
STRONG
assure attest authenticate aver avow commission corroborate okay profess reassure sanction show state swear testify vouch witness
WEAK
rubber-stamp
Antonyms
STRONGEST
deny disallow disapprove disprove invalidate oppose refuse reject veto
STRONG
conceal disclaim hide refute renounce
WEAK
contradict counteract disavow discredit repudiate

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

A senior defense official said on Tuesday that many at the Pentagon increasingly view Anthropic as a supply-chain risk and might ask contractors and vendors to certify that they don’t use the company’s Claude models.

From The Wall Street Journal • Feb. 18, 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

Now he has a degree to certify his nosiness.

From "On the Come Up" by Angie Thomas