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Synonyms

number one

American  

noun

number ones plural
  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

Other Word Forms

Noun Inflected Forms

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.

See Examples For:

You may remember what Angels owner Arte Moreno said in spring training: “The number one thing fans want is affordability.”

From Los Angeles Times Jul. 29, 2026

My number one goal now is to build bridges and maintain a relationship with families, because that’s what’s going to allow me to convince some of them.

From Los Angeles Times Jul. 28, 2026

Scheffler has been world number one since 21 May 2023 - nearly 166 weeks.

From BBC Jul. 27, 2026

She rose to global stardom with her 1972 album "No Secrets," which spawned the number one smash "You're So Vain."

From Barron's Jul. 27, 2026

I’ve already got number two down, but following number one and three haven’t gone so well.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

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