plung·er 
(plŭnjər)
(plŭnjər)n.
1. One who plunges or dives.
2. A device consisting of a rubber suction cup attached to the end of a stick, used to unclog drains and pipes. Also called plumber's helper.
3. A part of a machine, tool, or device that operates wtih a thrusting or plunging movement, such as a piston.
- superclass
- supercluster
- supercoil
- supercollider
- supercolony
- supercomputer
- superconduct
- superconducting
- superconductive
- superconductivity
- superconductor
- supercontinent
- supercool
- supercritical fluid
- supercurrent
- superdelegate
- superdense
- superdominant
- superduper
- superego
- supereminence
- supereminent
- supereminently
- supererogate
- supererogation