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

The 23-year-old British number one left New York before his second-round match because the discomfort in his arm had become too much.

From BBC

When Carlos Alcaraz won his sixth Grand Slam title on Sunday, he did so by thoroughly outclassing the world's number one player in probably the best performance of his career so far.

From BBC

"To be the number one at United you need to have rhino skin," said Phil Jones, who made 229 appearances in 12 seasons at the club, mostly in defence.

From BBC

The way in which the 22-year-old regained the US Open title and number one ranking has been a product of the intense work he has done to develop his game.

From BBC

Alcaraz has also wrestled the world number one ranking away from Sinner, who held the position for 65 weeks.

From BBC

Related Words

• champion 
• winner