What does "plunger" mean?

Plunger: A long solid cylinder, used, instead of a piston or bucket, as a forcer in pumps.

Additional senses

  1. 2.One who bets heavily and recklessly on a race; a reckless speculator. [Cant]
  2. 3.(Pottery) A boiler in which clay is beaten by a wheel to a creamy consistence. Knight.
  3. 4.(Gun.) The firing pin of a breechloader. Plunger bucket, a piston, without a valve, in a pump. -- Plunger pole, the pump rod of a pumping engine. -- Plunger pump, a pump, as for water, having a plunger, instead of a piston, to act upon the water. It may be single-acting or double- acting

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