| 1. | oneself, esp. 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. | of the highest in quality, status, importance, etc.; first-rate: a number one performance. |
| 4. | first in rank, order, or prestige: the number one book on the bestseller list. |
| 5. | urination: used esp. by or with reference to children. |
| 6. | make, do, or go number one, Informal. to urinate: used esp. by or with reference to children. |

| number one n.
|
number one
|