disk-wheel

from The Century Dictionary.

• noun A worm-wheel in which a spiral thread on the face of the disk drives a spur-gear the space of one tooth at each revolution, the shafts of the disk and gear being at right angles to each other.
• noun A type of wheel for cars or motor-vehicles in which the hub is connected to the rim by a continuous web or plate, instead of by spokes with open intervals between.