- a mechanism consisting of a worm engaging with and driving a worm wheel, the two axes usually being at right angles, used where a relatively low speed and a relatively large amplification of power are desired.
- a gear wheel driven by a worm.
- a device consisting of a threaded shaft (worm) that mates with a gearwheel (worm wheel) so that rotary motion can be transferred between two shafts at right angles to each other
- a gearwheel driven by a threaded shaft or worm
