number one

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.

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.

number one

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

adjective

1. first in importance, urgency, quality, etc

   number one priority

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

Word History and Origins

Origin of number one¹

First recorded in 1830–40

Idioms and Phrases

Idioms

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

Example Sentences

There were "two completely separate tours" in the 1980s and 1990s, according to former British number one Jeremy Bates: those who played on the clay, and those who played on the fast courts.

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"The number one problem about deporting illegal immigrants, first of all, is finding a place which will take them and which is not unsafe," argues Lord Sumption.

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Thomas Tuchel says "the race is on" to be England's number one, but is Jordan Pickford's place really under any serious threat - and just how good is he?

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The British number one will soon begin preparations in earnest for next season, having only been able to play one singles match since Wimbledon because of bone bruising in his left arm.

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Former world number one Novak Djokovic, who has slimmed down his schedule in recent years to protect his body, has called on players to be more united, external in forcing change.

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Related Words

• champion 
• winner