sure 1 of 2

adjective

ˈshu̇r How to pronounce sure (audio)
Definition of surenext
1
as in confident
having or showing a mind free from doubt are you absolutely sure that she said she was coming today?

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms
2
as in necessary
impossible to avoid or evade the joke's a sure dud if you don't pause in the right places

Synonyms & Similar Words

Antonyms & Near Antonyms
3
as in reliable
not likely to fail a sure cure for the winter blues—a week in the Bahamas

Synonyms & Similar Words

Antonyms & Near Antonyms
4
as in true
worthy of one's trust a sister is a sure friend for life

Synonyms & Similar Words

Antonyms & Near Antonyms
5
as in conclusive
not capable of being challenged or proved wrong no sure evidence that life exists on other planets

Synonyms & Similar Words

Antonyms & Near Antonyms

sure

2 of 2

adverb

as in definitely
without any question we sure could use your help here

Synonyms & Similar Words

Synonym Chooser

How does the adjective sure contrast with its synonyms?

Some common synonyms of sure are certain, cocksure, and positive. While all these words mean "having no doubt or uncertainty," sure usually stresses the subjective or intuitive feeling of assurance.

felt sure that I had forgotten something

When is certain a more appropriate choice than sure?

In some situations, the words certain and sure are roughly equivalent. However, 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 sure?

The words cocksure and sure can be used in similar contexts, but cocksure implies presumptuous or careless positiveness.

you're always so cocksure about everything

Where would positive be a reasonable alternative to sure?

The synonyms positive and sure are sometimes interchangeable, but positive intensifies sureness or certainty and may imply opinionated conviction or forceful expression of it.

I'm positive that's the person I saw

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 sure
Adjective
Engineers aren’t sure yet what caused the emergency with the Link spacecraft last weekend. — Stephen Clark, ArsTechnica, 1 Aug. 2026 At the moment, not sure anyone is taking on that contract without significant sweeteners, the type of sweeteners the Heat largely lack. — Ira Winderman, Sun Sentinel, 1 Aug. 2026
Adverb
The AirPods 4 with Active Noise Cancellation might've taken the Editors' Choice title for their extra frills, but these entry-level buds sure hold their own in the open-ear category. — Kelsey Fogarty, PC Magazine, 1 July 2026 If anything, the future Hall of Famer sure appeared to enjoy his time back home, which was a major reason why Leonard initially turned down a royal life in Canada to play for Southern California’s other team. — Joaquin Ruiz, Los Angeles Times, 30 June 2026 See All Example Sentences for sure
Recent Examples of Synonyms for sure
  1. confident
  2. necessary
  3. reliable
  4. true
  5. conclusive
  6. definitely
  7. certain
  8. inevitable
Adjective
  • Welcome to Style Forecast, a monthly horoscope that uses astrology to help each zodiac sign feel like their most confident and aligned self.
    — Meghan Rose, Glamour, 1 Aug. 2026
  • What’s the most recent segment that had you a little less confident?
    — Mikey O'Connell, HollywoodReporter, 31 July 2026
Definition of confident
Adjective
  • If monoculture is partially abandoned in certain areas, financial compensation will be necessary.
    — ABC News, ABC News, 31 July 2026
  • And Cristobal will do what is necessary to make sure that standard is established before the season begins.
    — Jordan McPherson, Miami Herald, 31 July 2026
Definition of necessary
Adjective
  • Comedy Central became one of TV’s most reliable stand-up farm systems beginning in the 1990s, implementing a mix of showcases, half-hours, roasts, late-night blocks and festival tie-ins to elevate the medium.
    — Matt Grobar, Deadline, 30 July 2026
  • After hiring a small 50-person crew as a test run, the railroad company found Chinese laborers to be reliable and efficient.
    — Sacbee.com, Sacbee.com, 30 July 2026
Definition of reliable
Adjective
  • Instead, the shoreline is made up of rocky outcroppings, making the pools—and the views—the true focal point.
    — Condé Nast, Condé Nast Traveler, 3 Aug. 2026
  • Thankfully for Chad Gable, his loss came in the match of the year in 2026, and this led to a babyface redemption tour with Chad Gable playing his true self as opposed to a heel luchador.
    — Alfred Konuwa, Forbes.com, 3 Aug. 2026
Definition of true
Adjective
  • In case of a nuclear attack on the US, nuclear forensics experts will have to investigate the incident and arrive at conclusive proof of where the material originated from.
    — Ameya Paleja, Interesting Engineering, 31 July 2026
  • So, a strange ending for one of Netflix’s best shows, but three seasons and a conclusive movie are now in Netflix’s catalog for anyone to watch.
    — Paul Tassi, Forbes.com, 25 July 2026
Definition of conclusive
Adverb
  • Snorkeling is definitely out—the deadly air notwithstanding—but perhaps walking along the bottom of a methane lake would be a fun diversion.
    — Phil Plait, Scientific American, 31 July 2026
  • The game definitely has more than a little cell-stage Spore in it.
    — ArsTechnica, ArsTechnica, 31 July 2026
Definition of definitely
Adjective
  • Trump on Monday announced plans to impose a 50% tariff on certain Canadian imports, citing what officials called trade discrimination against American companies in the dairy, auto and alcohol industries.
    — Bonny Chu, FOXNews.com, 22 July 2026
  • Now, after mounting the American League’s second-best record since June 1, the picture is less certain.
    — Cody Stavenhagen, New York Times, 22 July 2026
Definition of certain
Adjective
  • That hour made clear that isolation is not an inevitable side effect of hospitalization, but rather a consequence of a care delivery structure that can, and should, change.
    — Anna Tsioulias, STAT, 29 July 2026
  • In the fickle economy of online fame, the Tates’ total saturation had an inevitable sell-by date.
    — Dan Adler, Vanity Fair, 29 July 2026
Definition of inevitable

Phrases Containing sure

Browse Nearby Words

surd
sure
sure-enough
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Cite this Entry

“Sure.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/sure. Accessed 4 Aug. 2026.

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Nglish: Translation of sure for Spanish Speakers

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