number one

American  

noun

1. oneself, especially one's own well-being or interests.

   to look out for number one.

2. a person, company, etc., that is first in rank, order, or prestige.

   Our team is number one.

3. urination: used especially by or with reference to children.

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adjective

1. of the highest in quality, status, importance, etc.; first-rate.

   a number one performance.

2. first in rank, order, or prestige.

   the number one book on the bestseller list.

idioms

1. make / do / go number one, to urinate: used especially by or with reference to children.

number one British  

noun

1. the first in a series or sequence

2. an informal phrase for oneself myself

   to look after number one

3. informal the most important person; leader, chief

   he's number one in the organization

4. informal the bestselling pop record in any one week

5. euphemistic the act or an instance of urination

6. a haircut in which the hair is cut very close to the head with an electric shaver

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adjective

1. first in importance, urgency, quality, etc

   number one priority

2. informal (of a pop record) having reached the top of the charts

Etymology

Origin of number one

First recorded in 1830–40

Example Sentences

He accepts Rightmove is the "number one portal" but said costs shouldn't be determined by the company.

From BBC

Of all the neighbors to avoid, she’s number one, but it’s not because I don’t like her.

From Literature

Dangerously, it takes car smashes for the problematic side of the former world number one's life to be revealed.

From BBC

Emerging with the number one ranking would be an added bonus.

From BBC

Woods' high-speed single vehicle crash near Los Angeles nearly cost the former world number one his right leg.

From BBC

Related Words

• champion
• winner