Pronunciation: (pru-pel'ur),[key] —n. 1. a device having a revolving hub with radiating blades, for propelling an airplane, ship, etc.
2. a person or thing that propels.
3. the bladed rotor of a pump that drives the fluid axially.
4. a wind-driven, usually three-bladed, device that provides mechanical energy, as for driving an electric alternator in wind plants.