worm drive

A worm and wheel, a gear arrangement consisting of a screw (the worm) whose thread meshes with a gear wheel to turn the direction of drive through a right angle, typically with a large (1:10 to 1:60) speed reduction and similar torque increase.

(computer hardware) A write once, read many drive; data storage technology that allows information to be written to a disc a single time and prevents the drive from erasing the data.