| 1. | a system involving only two elements, as 0 and 1 or yes and no. |
| 2. | Mathematics. a system of counting or measurement whose units are powers of two. Compare binary (def. 2a). |
| 3. | Astronomy. binary star. |
| a system of two stars that revolve about their common center of mass. |
| binary number system n. A method of representing numbers in which only the digits 0 and 1 are used. Successive units are powers of 2. Also called binary system. |
| binary system n. See binary number system. |
