sure

- definition

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adjective

/ʃɔː(r)/

/ʃʊə(r)/

adjective	sure
comparative	surer
superlative	surest

1
certain that something is real, true, or correct
I think she’s called Monica, but I’m not sure.
sure (that):
Are you sure these figures are right?
sure (that):
I was sure that I had left my keys on the counter.
sure about:
If you’re really sure about the facts, we’ll publish them.
sure how/why/if etc:
No one is really sure why he resigned.
pretty sure (=fairly certain):
I’m pretty sure the pool is open until 6.00.
Thesaurus entry for this meaning of sure
1. a.
  certain about what you feel, what you want, or what you have decided
  ‘I’ll take the blue one.’ ‘Are you sure?’
  not sure how/why/where etc:
  They’re not really sure where they want to live.
  quite/absolutely sure:
  I’ll certainly support you, if you’re quite sure that this is what you want.
  Thesaurus entry for this meaning of sure
2. b.
  confident and not in any doubt about something
  sure of:
  If you’re not sure of the answers, say so.
  sure of yourself:
  He sounded so sure of himself that I began to believe him.
  feel sure (that):
  I felt sure I could do it if only they’d give me a chance.
  Thesaurus entry for this meaning of sure
2
certain to happen or to result from something
sure to do something:
If you get drunk tonight, you’re sure to feel rotten in the morning.
a sure thing/bet (=something that will definitely happen):
Everyone thought it was a sure thing, and we were amazed when they pulled out.
for sure:
One thing is for sure, I’m never going skydiving again!
Thesaurus entry for this meaning of sure
1. a.
  [usually before noun] formal certain to succeed
  He took sure aim and squeezed the trigger.
  a sure path to success
  Thesaurus entry for this meaning of sure
3
strong and firm
in the sure grip of a powerful emotion
His handshake was sure and confident.
Thesaurus entry for this meaning of sure
4
used about something that is definite and cannot be questioned or doubted
a sure command of the facts
a sure memory for names
a sure sign/indication (=a clear and definite sign that something is true):
The increase in new home sales is a sure sign the recession is over.
Thesaurus entry for this meaning of sure

phrases

be sure to do something
spoken
used for reminding someone to do something
Be sure to fasten your seat belt.
Thesaurus entry for this meaning of sure
make sure
1. 1
  to check something so that you can be sure about it
  I think I locked it but we’d better make sure.
  make sure (that):
  I just wanted to make sure you knew where to go.
  make sure of:
  Always make sure of your facts before accusing anyone.
  Thesaurus entry for this meaning of sure
2. 2
  to take the action necessary to be sure that something will happen or be done
  make sure (that):
  Police were there to make sure there was no violence.
  Thesaurus entry for this meaning of sure
sure thing
spoken
1. 1
  used for agreeing to something
  ‘Can you give me a hand moving this table?’ ‘Sure thing.’
  Thesaurus entry for this meaning of sure
2. 2
  American used as a reply when someone thanks you
  ‘Thanks for your call, Joe.’ ‘Sure thing.’
  Thesaurus entry for this meaning of sure
to be sure
spoken formal
used for admitting that something is true, before you say something that seems to be the opposite of this
To be sure, most people are law-abiding, but crime remains a problem.
Thesaurus entry for this meaning of sure

derived word

sureness

noun [uncountable]

Expressing yourself: sure

Examples:

I’m sure she won’t forget – she’s very reliable.

I’m positive I had the keys with me when I left. ♦ We’re certain we made the right decision. ♦ I know for a fact that he lied to me about the party.

You’re going to enjoy the show – I just know you are.

I bet they’ve gone without us! ♦ I bet he’s not as good a cook as you.

You will no doubt be relieved to hear that the management has agreed to your request.

Having examined the evidence, we are satisfied that safety regulations were not broken.

Expressing yourself: sure

Examples:

I think that’s what he said, but I can’t be certain. It was very noisy.

‘Do you think it will rain?’ ‘Maybe. We usually get lots of rain at this time of year.’

I wondered if perhaps he’d forgotten to confirm the booking.

As far as I know, he’s coming. But I haven’t spoken to him for weeks.

There’s no telling what she will do next. She’s so unpredictable.

This is the British English definition of sure. View American English definition of sure.

Change your default dictionary and thesaurus to American English.

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