noun
- a person or thing that impels.
- a rotor for transmitting motion, as in a centrifugal pump, blower, turbine, or fluid coupling.
noun
- the vaned rotating disc of a centrifugal pump, compressor, etc
- a compressor or centrifugal pump having such an impeller
1680s, agent noun from impel (v.). As a machine part from 1890.