1

number one

noun
Updated on: 11 Sep 2017

Definition of number one

1 :one's own interests or welfare :oneself
  • looking out for number one
often written No. 1
2 :one that is first in rank, importance, or influence often written No. 1

Examples of number one in a Sentence

  1. Who's number one in this office?

  2. Getting the car fixed is number one on my list of priorities.

  3. I'll tell you why we can't go on a vacation: number one, we can't afford it, and number two, we'll miss my sister's party.

  4. Her movie is currently number one at the box office.

  5. When the goal was scored, the fans started to chant, We're number one, we're number one.

  6. I've been taking care of other people for too long. It's time for me to take care of number one.

First Known Use of number one

circa 1705


2

number one

adjective

Definition of number one

1 :first in rank, importance, or influence :foremost
  • cancer is the country's number one killer
often written No. 1
2 :of highest or of high quality

Examples of number one in a Sentence

  1. The book is the company's number one seller.

  2. Rule number one is don't get caught!

  3. He's public enemy number one: the nation's most wanted criminal.

First Known Use of number one

1839


NUMBER ONE Defined for English Language Learners

number one

noun

Definition of number one for English Language Learners

  • : a person, thing, or position that is highest in rank : the most important person or thing in a group of people or things

  • : the most successful person or thing in a group of people or things

  • : your own happiness, health, or success


number one

adjective

Definition of number one for English Language Learners

  • : highest in rank or importance


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