| 1. | the ratio of the rotational speeds of the first and final gears in a train of gears or of any two meshing gears. |
| 2. | the ratio of the diameters of the pitch surfaces of any two meshing gears or of the numbers of their teeth. |

| gear ratio n. The ratio of the speed of rotation of the powered gear of a gear train to that of the final or driven gear. |