One

/wʌn/

determinerBeginner🔥Very CommonGeneral
4 meanings5 idioms/phrases4 questions

Definitions

4 meanings
1

Denoting a single unit or individual.

/wʌn/

determinerneutralBeginner
General

The cardinal number between zero and two.

I have one brother.

💡 Simply: Like when you have just one cookie, or when you're first in line! It's about having a single thing.

👶 For kids: One means just a single thing. Like, one toy, or one friend.

More Examples

2

There is one way to solve this problem.

3

She bought one ticket.

How It's Used

General

"I have one apple."

Mathematics

"One plus one equals two."

2

The number 1.

/wʌn/

nounneutralBeginner
General

The number or figure 1.

The sum of the numbers is one.

💡 Simply: It's the name of the number 1. When you write it, you're writing 'one'.

👶 For kids: One is the name of the number that means just one thing.

More Examples

2

She drew a one on her paper.

How It's Used

Mathematics

"The answer is one."

Games

"He scored a one in the dice roll."

Tip:Picture the numeral 1.
3

Referring to an unspecified person or thing.

/wʌn/

pronounneutralmedium
General

Used to refer to a person or thing previously mentioned or easily identified.

One should always be polite.

💡 Simply: It's like saying 'you' or 'people' in a general way. For example, 'One should always wash their hands' means anyone should.

👶 For kids: When we use 'one' to talk about people in general.

More Examples

2

One cannot predict the future.

3

One might think it is easy.

How It's Used

General

"One must always be kind."

Formal

"One does not simply walk into Mordor."

Tip:Think of a general, unspecified subject.
4

Being or amounting to a single unit or individual or entire thing, item, or amount.

/wʌn/

adjectiveneutralmedium
General

He had a one-track mind.

💡 Simply: When something is singular or exists as a single thing. For example, 'one way' or 'one choice'.

👶 For kids: When something is just a single thing, like one way to do something.

More Examples

2

The one thing that always works.

3

The one and only star.

How It's Used

General

"It was a one-time deal."

Shopping

"I want the one with the red cover."

Tip:Think of a single, unified entity.

Synonyms & Antonyms

Idioms & expressions

one by one

Individually, separately, or in succession.

"The soldiers marched into the camp one by one."

in one go

Without stopping; all at once.

"She ate the whole pizza in one go."

at one time

In the past.

"At one time, he was a famous actor."

one of a kind

Unique, special, or unmatched.

"She's one of a kind."

one-track mind

The ability to think of only one thing.

"He has a one-track mind when it comes to sports."

From Old English "ān" (masculine/neuter) and "ān" (feminine), from Proto-Germanic *ainaz, from Proto-Indo-European *óynos.

The Old English word "ān" was used to express singular quantity and continues to be used in modern English for the same purpose.

Memory tip

Think of the first thing you see – ONE.

Word Origin

LanguageProto-Germanic
Original meaning

"one, single"

one dayone timeone wayone personone thing

Common misspellings

won1onne

Usage

70%Spoken
30%Written