1

number one

noun

Definition of number one

  1. 1 :  one's own interests or welfare :  oneself looking out for number one —often written North 1

  2. 2 :  one that is first in rank, importance, or influence —often written North 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.

Circa 1705

First Known Use of number one

circa 1705


2

number one

adjective

Definition of number one

  1. 1 :  first in rank, importance, or influence :  foremost cancer is the country's number one killer —often written North 1

  2. 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.

1839

First Known Use of number one

1839


NUMBER ONE Defined for English Language Learners

1

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


2

number one

adjective

Definition of number one for English Language Learners

  • : highest in rank or importance


Learn More about number one


Seen and Heard

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