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
Going into the 2024 season, Heinzerling was not entirely sure of the narrative for the doc, as Nadal was returning to tennis after a hip surgery. — Caitlin Huston, HollywoodReporter, 9 Aug. 2026 Worse, the researchers aren’t sure whether changing Chrome’s password manager PIN or deleting all of Chrome’s password manager data will actually invalidate any access a hacker may already have obtained. — Alan Henry, PC Magazine, 7 Aug. 2026
Adverb
Because a versatile, full-size 1,000-mile (1,600-km) electrified SUV that just happens to integrate full sleeping and dining accommodations sure sounds like an impressive evolution of the camper to us. — New Atlas, 6 Aug. 2026 That song features a special guest, credited under the pseudonym Son-John Johnson, who sure sounds a lot like Geese’s Cameron Winter — another indie singer-songwriter who often seems ambivalent about being put under the microscope of fame. — Angie Martoccio, Rolling Stone, 5 Aug. 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
  • In the long run, leaders are confident the 19 new boats will prove suitable replacements for the Ohios.
    — Brad Lendon, CNN Money, 8 Aug. 2026
  • These signals, coupled with the Jassy masterclass, made the market feel more confident that capex from the spenders hasn't peaked yet, which is good for the vendors.
    — Kevin Stankiewicz, CNBC, 7 Aug. 2026
Definition of confident
Adjective
  • Tether defends the short delay as a necessary trade-off for responsible responsiveness in a large ecosystem, rejecting claims of a loophole.
    — Boaz Sobrado, Forbes.com, 8 Aug. 2026
  • Every Fathom, even the most barebones, will have the hardware and sensors necessary to turn on BlueCruise, the company’s software that enables drivers to take their hands off the wheel while on the highway.
    — Michael Ballaban, CNN Money, 7 Aug. 2026
Definition of necessary
Adjective
  • Demand planning capabilities on the Blue Yonder Platform utilize patented algorithms and advanced machine learning models to ensure that demand forecasting is not only highly accurate, but reliable.
    — Arthur Zaczkiewicz, Footwear News, 13 Aug. 2026
  • Later reports would place the bear’s weight as high as 600 pounds, but the most reliable estimates were less than 250.
    — Paul Schullery, Outdoor Life, 13 Aug. 2026
Definition of reliable
Adjective
  • But regardless of any lack of confidence in Hamas’ true intentions, in Mladenov’s faith in the ability to verify weapons decommissioning, or indeed Netanyahu’s own willingness to order any troop withdrawals, why poke Trump so publicly in the eye?
    — Andrew Carey, CNN Money, 10 Aug. 2026
  • This problem-first strategy is crucial for unlocking AI's true potential.
    — Bernard Marr, Forbes.com, 10 Aug. 2026
Definition of true
Adjective
  • The opposite mistake is to treat every statistical change or customer complaint as conclusive evidence of material harm.
    — Gerald J. Leonard, Forbes.com, 10 Aug. 2026
  • There’s less conclusive evidence that microdosing works the same way by engaging the same neuro-receptors, but less intensely.
    — Helen Carefoot, Flow Space, 5 Aug. 2026
Definition of conclusive
Adverb
  • In a region where air conditioning runs for months at a time, the savings definitely add up.
    — Quincy Bulin, Southern Living, 7 Aug. 2026
  • The song’s pace changed from a blitz into a groove, not so much a mosh part, but definitely more danceable.
    — Literary Hub, Literary Hub, 7 Aug. 2026
Definition of definitely
Adjective
  • Some states, including Maryland, prohibit certain hospitals from requiring prepayment simply to avoid offering financial assistance.
    — Julie Appleby, CBS News, 12 Aug. 2026
  • Rather than relying purely on attacking returns or clean sheets, players can now earn additional FPL points by reaching certain defensive thresholds.
    — Abdul Rehman, New York Times, 12 Aug. 2026
Definition of certain
Adjective
  • When Russia launched its full-scale invasion in 2022, Ukraine intentionally sank its last major ship rather than accept an inevitable takeover by Russia's large Black Sea fleet.
    — Greg Myre, NPR, 13 Aug. 2026
  • Any peace process will face inevitable setbacks and sabotage attempts, and so the parties must be committed to talks to get them over the line.
    — Matt Waldman, Foreign Affairs, 13 Aug. 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 14 Aug. 2026.

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Nglish: Translation of sure for Spanish Speakers

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