determiner

one

one, a single

She has one dog.

She has one dog.

I like the blue one.

I like the blue one.

One must be careful.

One must be careful.

((noun)) as a number before a noun I have one cat.

((pronoun)) to replace a previously mentioned noun Which one do you want?

((impersonal pronoun)) to mean 'people in general' One should always tell the truth.

Synonyms (as pronoun): a person, an individual; Antonyms (as number): two, many, none

From Proto-Indo-European root '*oi-no-' meaning 'one, unique'.

The pronunciation sounds like 'won', not like 'own'. It's the first and most basic number.

This page is designed for learning support. Please use it as a learning reference, not as a formal reference.