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Synonyms

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. first in importance, urgency, quality, etc

    number one priority

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of number one

First recorded in 1830–40

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"We are number one because we have a soul and not just money, and our guys at the front prove it every day," he said in a recent show.

From Barron's

As well as being number one on YouTube, Eminem was more popular on Spotify in the Welsh capital than in any other city, in ninth.

From BBC

Yet the game could mirror the 2021 win over England, which sparked Ireland's first rejuvenation under Farrell before they reached world number one in 2023.

From BBC

Meanwhile world number one Scottie Scheffler made the cut by the skin of his teeth to push his streak of cuts made to 68 -- the longest active streak on the PGA Tour.

From Barron's

The song - Fender's first ever chart-topping single - finally reached the summit on Friday, breaking the record for the most consecutive weeks in the top 40 before reaching number one.

From BBC