Meanings
How to pronounce "number one":
AU
First; foremost; best, often used after its headword.
Example: "Commuting to work is the number one reason to own a car."
Example: "He is my enemy number one."
The most important person, the one who is in charge.
Someone who is top of a ranking, who is ranked first.
Oneself, being considered foremost, as by an egoist.
Urine; urination.
Example Sentences
1
She is my number one priority in life.
2
John is number one in his class.
3
I want to be the number one tennis player in the world.
4
Safety should be our number one concern.
5
This book is number one on the bestseller list.