\ˈshu̇r, ˈshər, especially Southern ˈshȯr\
surer; surest

Definition of sure 

(Entry 1 of 2)

1 obsolete : safe from danger or harm

2 : firmly established : steadfast a sure hold

3 : reliable, trustworthy a sure friend

4a : marked by or given to feelings of confident certainty I'm sure I'm right

b : characterized by a lack of wavering or hesitation sure brush strokes a sure hand

5 : admitting of no doubt : indisputable spoke from sure knowledge

6a : bound to happen : inevitable sure disaster

b : bound, destined is sure to win

7 : careful to remember, attend to, or find out something be sure to lock the door

for sure

: without doubt or question : certainly

to be sure

: it must be acknowledged : admittedly



Definition of sure (Entry 2 of 2)

: surely

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Other Words from sure


sureness noun

Choose the Right Synonym for sure


sure, certain, positive, cocksure mean having no doubt or uncertainty. sure usually stresses the subjective or intuitive feeling of assurance. felt sure that I had forgotten something 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 positive intensifies sureness or certainty and may imply opinionated conviction or forceful expression of it. I'm positive that's the person I saw cocksure implies presumptuous or careless positiveness. you're always so cocksure about everything

Sure vs. Surely: Usage Guide


Most commentators consider the adverb sure to be something less than completely standard; surely is usually recommended as a substitute. Our current evidence shows, however, that sure and surely have become differentiated in use. Sure is used in much more informal contexts than surely. It is used as a simple intensive I can never know how much I bored her, but, be certain, she sure amused me — Norman Mailer and, because it connotes strong affirmation, it is used when the speaker or writer expects to be agreed with. it's a moot point whether politicians are less venal than in Twain's day. But they're sure as the devil more intrusive — Alan Abelson he sure gets them to play — D. S. Looney Surely, like sure, is used as a simple intensive I surely don't want to leave the impression that I had an unhappy childhood — E. C. Welsh but it occurs in more formal contexts than sure. Unlike sure it may be used neutrally—the reader or hearer may or may not agree it would surely be possible, within a few years, to program a computer to construct a grammar — Noam Chomsky and it is often used when the writer is trying to persuade. surely a book on the avant-garde cannot be so conventional — Karl Shapiro

Examples of sure in a Sentence


She's not sure who will be there. Are you sure you want to go? Are you sure about that? She'll be there, I'm sure of it. Are you sure of the results? The return of the robins is a sure sign of spring. The letter is a sure indication that she cares. Pizza is a sure crowd pleaser. The surest way to lose weight is with diet and exercise. One sure way to improve your health is to stop smoking.


we sure could use your help here
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Recent Examples on the Web: Adjective

Make sure the details your agent have are accurate: the square footage, number of bedrooms and bathrooms, the type of flooring. Ron Hurtibise,, "Do you have enough homeowner insurance? Here's how to find out," 13 July 2018 Shop a tan or orange jumpsuit and make sure to create your own ID badge. Elizabeth Denton, Seventeen, "14 Genius Group Halloween Costume Ideas for You and Your Squad," 6 July 2018 The Shangchen finds are sure to encourage other researchers to hunt for further signs of hominins living in Eurasia before 2 million years ago, says Kappelman. Colin Barras, Scientific American, "Tools from China are Oldest Hint of Human Lineage Outside Africa," 11 July 2018 Be sure to walk by the Pumpkin House, a Victorian adorned with more than 3,000 gourds. Catherine Strawn, Country Living, "17 Amazing Halloween Celebrations Across America," 11 July 2018 Pearman said the county upgraded its internet bandwidth and thought steps were needed to make sure that was available to necessary applications. Craig Lyons, Post-Tribune, "Lake County moves to limit employees' internet use," 6 July 2018 After taking a few months to make sure the case was legally sound, Roca held a press conference last week so the media could hear Escotto's story. Colleen Wright, miamiherald, "Mom's secret recording catches kindergarten teacher calling 5-year-old a "loser"," 5 July 2018 This is extremely serious, but even more frightening is the sure knowledge that is this going to continue and is going to occur during the midterm elections and beyond. Fox News, "Alberto Gonzales: WH response to indictments is baffling," 13 July 2018 The result was the Toronto Declaration, which says companies need to make sure that machine learning does not extend discrimination. Joseph Menn, The Christian Science Monitor, "Silicon Valley employees increasingly push companies on ethics," 13 July 2018

Recent Examples on the Web: Adverb

The last, sure-fire (ha!) technique to control these diseases is to go to containers — big containers — and filling them with new, high quality, bagged growing mix. Paul Cappiello, The Courier-Journal, "Tomato — the 'luscious beauty' of the garden and how to fight diseases," 8 June 2018 Manfred would be delighted to add a team in Mexico and another in Montreal, but there are no sure-fire U.S. markets available. Bill Shaikin,, "Three up, three down: Ichiro Suzuki heads to front office; Astros closer Ken Giles struggles again," 5 May 2018 The broad answer is, sure, there’s always a way out of these things, there’s always a deal to be done. Emily Stewart, Vox, "Can the US-China trade war be stopped? 11 experts weigh in.," 8 July 2018 Part of the engineering of the show is making sure that the shells launch high enough that all the pyrotechnic reactions take place before the pieces reach the ground. Kevin Davenport, idahostatesman, "O say can you see? The science behind the booms and blooms of Independence Day fireworks," 3 July 2018 One thing is sure, however: Milton’s going to put up numbers. Paul Myerberg, USA TODAY, "The 10 best quarterbacks in college football," 26 June 2018 One challenge is making sure the charger doesn’t overheat. Fortune, "Why Apple's AirPower Wireless Charger Is Taking So Long to Make," 21 June 2018 State emergency officials are making sure more people will be alerted by phone of an approaching wildfire, having learned from Sonoma County’s failure to send out Amber Alert-style messages as October’s Wine Country fires bore down. Peter Fimrite,, "Firefighters demonstrate the danger of a Fourth of July sparkler," 19 June 2018 Making sure the spray evenly coats your hair is where things get tricky, though. Devon Abelman, Allure, "Color Wow Dream Coat for Curls Humidity-Proofs Your Hair," 18 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sure.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sure


13th century, in the meaning defined at sense 1


14th century, in the meaning defined above

History and Etymology for sure


Middle English seur, sure, from Anglo-French seur, from Latin securus secure

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Dictionary Entries near sure





sure bet

sure enough


Statistics for sure

Last Updated

3 Nov 2018

Look-up Popularity

Time Traveler for sure

The first known use of sure was in the 13th century

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More Definitions for sure



English Language Learners Definition of sure

 (Entry 1 of 2)

: not having any doubt about something : convinced or certain

: not allowing any doubt or possibility of failure

: known to be true or correct



English Language Learners Definition of sure (Entry 2 of 2)

—used to say “yes” or to agree to a request or suggestion

—used to disagree with a negative statement or suggestion

—used to emphasize that you agree with the first part of the statement that you are about to make


\ˈshu̇r \
surer; surest

Kids Definition of sure

 (Entry 1 of 2)

1 : having no doubt : certain … he could not be sure if the scream awakened him or the pain in his stomach.— Gary Paulsen, Hatchet

2 : true without question

3 : firmly established a sure grip

4 : reliable, trustworthy a sure remedy

5 : bound to happen sure disaster

6 : bound as if by fate You are sure to win.



Kids Definition of sure (Entry 2 of 2)

2 : surely sense 2 Sure, we'll be there. “Well, you sure gave me some bad moments. I almost passed out …”— Oliver Butterworth, The Enormous Egg

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full of whispering sounds

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