Meaning of ONE in English

ONE

/ wʌn; NAmE / number , determiner , pronoun

■ number , determiner

1.

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) .

2.

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.

3.

used for emphasis to mean 'a single' or 'just one' :

There's only one thing we can do.

4.

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.

5.

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.

6.

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.

7.

the same :

They all went off in one direction.

8.

( informal , especially NAmE ) used for emphasis instead of a or an :

That was one hell of a game!

She's one snappy dresser.

9.

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.

IDIOMS

- 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

■ pronoun

1.

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?

2.

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.

3.

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.

4.

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.

5.

( 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.

6.

a ˈone ( old-fashioned , especially BrE ) a person whose behaviour is amusing or surprising :

Oh, you are a one!

7.

the ~ about sth the joke :

Have you heard the one about the Englishman, the Irishman and the Scotsman?

IDIOMS

- be (a) one for (doing) sth

••

GRAMMAR

one

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.

••

WORD ORIGIN

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.

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.