Definition of certainnext
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 On Wednesday night, when Thursday’s pin locations were released, the local caddie barn began placing $100 wagers on players putting off certain greens. Brendan Quinn, New York Times, 16 May 2026 The Sex Work Autonomous Committee (SWAC) is hoping to use the uptick in business that has traditionally come with an F1 weekend to make a statement as the strippers fight to be treated as employees, which comes with a certain set of rights. Matt Reigle Outkick, FOXNews.com, 16 May 2026 At a certain point, ideological conviction probably functions like a performance-enhancing drug. Rachel Marsden, Hartford Courant, 16 May 2026 No one on the island, with the exception of certain high-ranking officials, can escape the challenges presented by the lack of oil, Piñon said. Julia Jacobo, ABC News, 16 May 2026 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
  • For a successful but not world-conquering rapper like Rashad, making a living relies on making sure that fans continue to feel connected to him.
    Kelefa Sanneh, New Yorker, 15 May 2026
  • Make sure you guys get your news from reputable sources!
    Nick Harris, Fort Worth Star-Telegram, 14 May 2026
Adjective
  • Composers from more stable lands nursed their own fears.
    Alex Ross, New Yorker, 18 May 2026
  • One victim suffered critical injuries but was in stable condition, while three others sustained non-life-threatening wounds.
    Greg Wehner, FOXNews.com, 18 May 2026
Adjective
  • Secure loose outdoor items and adjust plans as necessary so you're not caught outside.
    CA Weather Bot, Sacbee.com, 15 May 2026
  • Secure loose outdoor items and adjust plans as necessary so you’re not caught outside.
    Southern California Weather Report, Daily News, 15 May 2026
Adjective
  • Even recognizing one or two reliable triggers—like tight clothing, prolonged sitting or hot weather—can help guide meaningful adjustments.
    Lauryn Higgins, Flow Space, 11 May 2026
  • The dogs provide rangers with a reliable way to etch trails, haul supplies and even assist park scientists with snow-dependent research.
    K. R. Callaway, Scientific American, 11 May 2026
Adjective
  • Meeks said there was a definite measure of satisfaction derived from the project.
    Jim Woods, Chicago Tribune, 14 May 2026
  • From one set of perspectives, money is said to be a thing that exists in a definite quantity—ideally gold, but now bits on a computer; ensuring that the right amount of money exists is the only way to avoid a host of macro-economic problems.
    Literary Hub, Literary Hub, 13 May 2026
Adjective
  • Creating pieces that make women feel comfortable and confident through every stage of motherhood has always been at the core of Bumpsuit.
    Angela Velasquez, Footwear News, 14 May 2026
  • Silver benefits from both ‘risk-on’ and ‘risk-off’ environments ‘Risk-on’ describes markets where investors feel confident and chase growth.
    Sharon Wu, USA Today, 14 May 2026
Adjective
  • In a final battle, the Darksaber is destroyed, Gideon and his clones are seemingly killed, and the newly united Mandalorians settle back on Mandalore.
    Brendan Morrow, USA Today, 16 May 2026
  • Some see this as a way of making the World Cup final more accessible, leveraging it to a wider audience and taking the sport’s biggest moment to a higher level.
    Ben Church, CNN Money, 15 May 2026

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Cite this Entry

“Certain.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/certain. Accessed 19 May. 2026.

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