Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “number one”

See all translations

number one

noun [U] uk   us  

number one noun [U] (YOURSELF)

( US also numero uno) informal yourself and no one else: Frank is completely selfish - he only cares about number one. I'm going to look out for number one (= take care of myself only).

number one noun [U] (THE BEST)

the most important, best, most noticeable, or most famous person or organization in a particular area of activity: She's still the world number one in tennis. I'm your number one fan.
Translations of “number one”
in Chinese (Traditional) 自己…
in Chinese (Simplified) 自己…
(Definition of number one from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of number one?
Add Cambridge dictionaries to your browser to your website

Definitions of “number one” in other dictionaries

Word of the Day

piglet

a baby pig

Word of the Day

The way we move (Verbs for walking and running)

by Kate Woodford,
March 25, 2015
​​​ This week we’re looking at interesting ways to describe the way that people move. Most of the verbs that we’ll be considering describe how fast or slow people move. Others describe the attitude or state of mind of the person walking or running. Some describe both. Starting with verbs for walking slowly,

Read More 

stackin’ p

March 30, 2015
idiom slang earning a lot of money ‘That’s a very generous present.”Yeah, well, she’s stackin’ p, innit?’

Read More