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Related to plunger: pint, plunger lift


1. a rubber suction cup fixed to the end of a rod, used to clear blocked drains
2. a device or part of a machine that has a plunging or thrusting motion; piston



(also ram), a piston that has a smooth generatrix (generating surface) or annular grooves and is substantially longer than it is wide. Plungers are chiefly used in hydraulic machines, where they serve as components of pumps, of hydraulic presses and lifts, of slide valves in hydraulic drives, and of multistage gas compressors.


(design engineering)
A wooden shaft with a large rubber suction cup at the end, used to clear plumbing traps and waste outlets.
(mechanical engineering)
The long rod or piston of a reciprocating pump.

plumber’s friend, force cup, plumber’s helper, plunger

A tool consisting of a rubber suction cup attached to a handle; set over a plumbing trap (or the like) and worked with a pumping action to clear the trap of minor obstructions.
References in periodicals archive ?
Plungers are invited to join the conversation and share who they will #PlungeWith on Facebook, Twitter and Instagram.
Lastly, mark the firing pin plunger with Dykem or permanent marker and carefully reassemble the slide.
Hydraulic drive offers exceptional control, giving maximum power as setpoint is approached, yet allows the operator to slow the plunger pump to just a few rpms, virtually ensuring no overshoot.
The Rubbermaid Clean & Dry Plunger is exclusively protected with NeverWet nanotech coating, which forms a shield that repels water.
The XO explained that a serialized fuel-vent plunger, assigned to their aircraft, was found on the active runway during a FOD sweep.
Disc spring centralizers are added on the both sides of non-leakage sucker pump to solve the partial abrasion between the plunger and pump barrel for the unilateral wear of sealing ring caused by the uneven force.
It is presumed his plunger was seized as evidence, though it probably could have come in handy in his cellblock.
Specification Problem Recommendation Flow Rate Meeting accurate flow * Design plunger diameters rates is what drives the <2.
The best toilet plunger is one that's designed for a toilet.
3 -- Qosina has unveiled a 10 ml Open Bore Syringe (#C1105) and two 20 ml Open Ended Syringes (#C2500 and C2501), which are made of an ABS plunger, a Silicone plunger tip and a shatter-resistant Polycarbonate barrel that ensures visual clarity.