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adjective \ˈshu̇r, especially Southern ˈshȯr\

Simple Definition of sure

  • : not having any doubt about something : convinced or certain

  • : not allowing any doubt or possibility of failure

  • : known to be true or correct

Source: Merriam-Webster's Learner's Dictionary

Full Definition of sure



  1. 1 obsolete :  safe from danger or harm

  2. 2 :  firmly established :  steadfast <a sure hold>

  3. 3 :  reliable, trustworthy <a sure friend>

  4. 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. 5 :  admitting of no doubt :  indisputable <spoke from sure knowledge>

  6. 6a :  bound to happen :  inevitable <sure disaster>b :  bound, destined <is sure to win>

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



for sure

  1. :  without doubt or question :  certainly

to be sure

  1. :  it must be acknowledged :  admittedly

Examples of sure in a sentence

  1. She's not sure who will be there.

  2. Are you sure you want to go?

  3. Are you sure about that?

  4. She'll be there, I'm sure of it.

  5. Are you sure of the results?

  6. The return of the robins is a sure sign of spring.

  7. The letter is a sure indication that she cares.

  8. Pizza is a sure crowd pleaser.

  9. The surest way to lose weight is with diet and exercise.

  10. One sure way to improve your health is to stop smoking.

Origin and Etymology of sure

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

First Known Use: 13th century

Synonym Discussion of 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>.




Simple Definition of sure

  • —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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of sure

  1. :  surely

Usage Discussion of sure

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

  1. <we sure could use your help here>

14th Century

First Known Use of sure

14th century

SURE Defined for Kids



adjective \ˈshu̇r\

Definition of sure for Students



  1. 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. 2 :  true without question

  3. 3 :  firmly established <a sure grip>

  4. 4 :  reliable, trustworthy <a sure remedy>

  5. 5 :  bound to happen <sure disaster>

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




Definition of sure for Students

  1. 1 :  surely 1

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

Seen and Heard

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a dwelling place or home

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