/ wʌn; NAmE / number , determiner , pronoun
■ number , determiner
the number 1 :
Do you want one or two?
There's only room for one person.
One more, please!
a one-bedroomed apartment
I'll see you at one (= one o'clock) .
used in formal language or for emphasis before hundred , thousand , etc., or before a unit of measurement :
It cost one hundred and fifty pounds.
He lost by less than one second.
used for emphasis to mean 'a single' or 'just one' :
There's only one thing we can do.
a person or thing, especially when they are part of a group :
One of my friends lives in Brighton.
One place I'd really like to visit is Bali.
used for emphasis to mean 'the only one' or 'the most important one' :
He's the one person I can trust.
Her one concern was for the health of her baby.
It's the one thing I can't stand about him.
used when you are talking about a time in the past or the future, without actually saying which one :
I saw her one afternoon last week.
One day (= at some time in the future) you'll understand.
the same :
They all went off in one direction.
( informal , especially NAmE ) used for emphasis instead of a or an :
That was one hell of a game!
She's one snappy dresser.
used with a person's name to show that the speaker does not know the person
SYN a certain :
He worked as an assistant to one Mr Ming.
- as one
- (be) at one (with sb/sth)
- for one
- get sth in one
- get one over (on) sb/sth
- go one better (than sb/sth)
- in one
- one after another / the other
- one and all
- one and only
- one and the same
- one by one
- one or two
- one up (on sb)
- when you've seen, heard, etc. one, you've seen, heard, etc. them all
—more at all pronoun , minority , square noun
used to avoid repeating a noun, when you are referring to sb/sth that has already been mentioned, or that the person you are speaking to knows about :
I'd like an ice cream. Are you having one, too?
Our car's always breaking down. But we're getting a new one soon.
She was wearing her new dress, the red one.
My favourite band? Oh, that's a hard one (= a hard question) .
What made you choose the one rather than the other?
( BrE )
How about those ones over there?
used when you are identifying the person or thing you are talking about :
Our house is the one next to the school.
The students who are most successful are usually the ones who come to all the classes.
one of a person or thing belonging to a particular group :
It's a present for one of my children.
We think of you as one of the family.
one (to do sth) a person of the type mentioned :
10 o'clock is too late for the little ones .
He ached to be home with his loved ones .
She was never one to criticize.
( formal ) used to mean 'people in general' or 'I', when the speaker is referring to himself or herself :
One should never criticize if one is not sure of one's facts.
One gets the impression that they disapprove.
HELP NOTE : This use of one is very formal and now sounds old-fashioned. It is much more usual to use you for 'people in general' and I when you are talking about yourself.
a ˈone ( old-fashioned , especially BrE ) a person whose behaviour is amusing or surprising :
Oh, you are a one!
the ~ about sth the joke :
Have you heard the one about the Englishman, the Irishman and the Scotsman?
- be (a) one for (doing) sth
One / ones is used to avoid repeating a countable noun, but there are some times when you should not use it, especially in formal speech or writing:
1 After a possessive ( my , your , Mary's , etc.), some , any , both or a number, unless it is used with an adjective:
'Did you get any postcards?' 'Yes, I bought four nice ones.'
• I bought four ones.
2 It can be left out after superlatives, this , that , these , those , either , neither , another , which , etc.:
'Here are the designs. Which (one) do you prefer?' 'I think that (one) looks the most original.'
3 These ones and those ones are not used in NAmE , and are unusual in BrE :
Do you prefer these designs or those?
4 It is never used to replace uncountable nouns and is unusual with abstract countable nouns:
The Scottish legal system is not the same as the English system
, is better than
...as the English one.
Old English ān , of Germanic origin; related to Dutch een and German ein , from an Indo-European root shared by Latin unus . The initial w sound developed before the 15th cent. and was occasionally represented in the spelling; it was not accepted into standard English until the late 17th cent.