1
as in one
known but not named a certain person told me that today is your birthday

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

2
3
4
5
as in reliable
not likely to fail chicken soup is grandma's certain cure for pretty much whatever ails you

Synonyms & Similar Words

Antonyms & Near Antonyms

6

Synonym Chooser

How does the adjective certain contrast with its synonyms?

Some common synonyms of certain are cocksure, positive, and sure. While all these words mean "having no doubt or uncertainty," certain may apply to a basing of a conclusion or conviction on definite grounds or indubitable evidence.

police are certain about the cause of the fire

When would cocksure be a good substitute for certain?

In some situations, the words cocksure and certain are roughly equivalent. However, cocksure implies presumptuous or careless positiveness.

you're always so cocksure about everything

When is it sensible to use positive instead of certain?

While the synonyms positive and certain are close in meaning, positive intensifies sureness or certainty and may imply opinionated conviction or forceful expression of it.

I'm positive that's the person I saw

When could sure be used to replace certain?

The words sure and certain are synonyms, but do differ in nuance. Specifically, sure usually stresses the subjective or intuitive feeling of assurance.

felt sure that I had forgotten something

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 certain This test uses fluorescent dyes that only attach to certain parts of a chromosome. Anna Giorgi, Verywell Health, 14 July 2025 The office will also be able to review certain materials with protections. Jake Sheridan, Chicago Tribune, 14 July 2025 Opening certain shows along the route are Trace Mountains, Jawdropped, and Subtle Orange. Nina Corcoran, Pitchfork, 14 July 2025 A number of Republicans that represent states with rural communities -- such as Sens. Lisa Murkowski of Alaska and Mike Rounds of South Dakota -- have expressed concerns about cuts to public broadcasting that could affect the ability of certain communities to access emergency alerts. Allison Pecorin, ABC News, 14 July 2025 See All Example Sentences for certain
Recent Examples of Synonyms for certain
Adjective
  • Drinkwater didn't make one appearance in a Chelsea shirt last season, whilst Bakayoko spent the season in Italy on loan at AC Milan.
    SI.com, SI.com, 3 Aug. 2019
  • Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
    Johannes Himmelreich, BostonGlobe.com, 30 Mar. 2018
Adjective
  • Going into the conversation, Alicia wasn’t sure how Amelia would respond.
    Jordan Greene, People.com, 11 July 2025
  • The Cheever review may be my last, but who knows for sure?
    John Updike, New Yorker, 11 July 2025
Adjective
  • The president further argues that lower rates will make financing the ever-increasing federal debt cheaper, a factor which does not play into the Fed’s statutory dual mandate of ensuring maximum sustainable employment and stable prices.
    Ron Insana, CNBC, 11 July 2025
  • His early stardom never quite translated into a stable senior career as opportunities dried up in a system overflowing with talent.
    Los Angeles Times, Los Angeles Times, 11 July 2025
Adjective
  • Of course the private sector can price assets correctly of its own accord, and if riskless securities are necessary for this purpose, the private sector can produce them.
    Brian Domitrovic, Forbes.com, 6 July 2025
  • Eduardo Cavaliere, Rio’s vice mayor, said in an interview that the rules were necessary to impose some order to a sometimes chaotic scene.
    Dado Galdieri, New York Times, 6 July 2025
Adjective
  • By offering reliable transit to healthcare facilities and supporting the academic missions of San Jose State and Santa Clara University with low-cost transit options, the project fosters a more connected community and provides new opportunities for residents.
    Rowan Briggs, Mercury News, 10 July 2025
  • Best Buy Here's proof that reliable tracking doesn't have to be expensive.
    Adrienne So, Wired News, 10 July 2025
Adjective
  • The video is generally crisp, though the limited frame rate (15 fps) is a definite weakness with moving subjects.
    Simon Hill, Wired News, 11 July 2025
  • There are definite reasons to question Rodgers' commitment to the Steelers.
    Evan Massey, MSNBC Newsweek, 9 July 2025
Adjective
  • But whether the team would be confident elevating an interim replacement the way the Nats did with assistant GM Mike DeBartolo is not known.
    Ken Rosenthal, New York Times, 8 July 2025
  • And for those stunning backless dresses that demand a bra-free look, nipple covers are your secret weapon for confident coverage.
    Caitlyn Martyn may earn a commission if you buy through our referral links. This content was created by a team that works independently from the Fox newsroom., FOXNews.com, 8 July 2025
Adjective
  • As most readers already know, the Beatles’ final U.S. tour closed the door on touring altogether.
    John Tamny, Forbes.com, 2 July 2025
  • On the eve of USAID’s final day, former Presidents George W. Bush and Barack Obama gathered with former staffers as well as U2 singer and humanitarian Bono on a video call.
    Chad de Guzman, Time, 1 July 2025

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Cite this Entry

“Certain.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/certain. Accessed 18 Jul. 2025.

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