guess - Definition from Longman English Dictionary Online

Date:	1200-1300
Origin:	Probably from a Scandinavian language

guess
1 verb

guess1 S1 W3 See pronunciation table in "How to use dictionary" pages

1 [intransitive and transitive] to try to answer a question or form an opinion when you are not sure whether you will be correct:

Look up a word starting with D or S for samples of headword or sentence pronunciations on the LDOCE CD-ROM

I'd say he's around 50, but I'm only guessing.

guess right/correctly/wrong

If you guess correctly, you have another turn.

guess what/who/how etc

You can guess what happened next.

guess at

We can only guess at the cause of the crash.

What star sign are you? No, let me guess.

difficult/hard/easy etc to guess

It's hard to guess his age because he dyes his hair.

2 [intransitive and transitive] to realize that something is true even though you do not know for certain

guess (that)

I guessed that you must be related because you look so similar.

guess from

I guessed from his expression that he already knew about the accident.

Can you guess the identity of this week's special guest?

keep somebody guessing

to make someone feel excited or not sure about what will happen next:

a thriller that keeps audiences guessing

I guess

spoken

a) used to say that you think something is true or likely, although you are not sure:

His light's on, so I guess he's still up.

b) used to say that you will do something even though you do not really want to:

I'm tired, so I guess I'll stay home tonight.

I guess so/not

spoken used to agree or disagree with a statement or question:

'You're one lucky guy.' 'I guess so.'

'I don't really have any choice, do I?' 'I guess not.'

guess what/you'll never guess who/what etc

spoken used before you tell someone something that will surprise them:

Guess what! Bradley's resigned.

You'll never guess who I saw today.

➔ second-guessWORD CHOICE:

WORD CHOICE:

suppose, guessIn spoken phrases, I suppose and I guess are used in the same way, but suppose is more usual in British English and guess in American English • I suppose that's his mum. • I guess you're right. • I suppose you can come if you want to. • I guess I'll go home now. • 'Should we sit here?' 'I suppose so.' • 'Isn't he coming?' 'I guess not.'GRAMMAR!! Do not say 'be suppose to do something'. Use be supposed to • You're supposed to take your shoes off. • He's supposed to be very clever. ➔ See also suppose

Definition from the Longman Dictionary of Contemporary English
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