Definition of "plunger" [plun•ger]

• One who plunges or dives. (noun)
• 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. (noun)
• A machine part, such as a piston, that operates with a thrusting or plunging movement. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Once the plunger is in place mix it around a bit as this will stop the grounds from settling in one place at the top of the jar and then after a minute or so you can then press the plunger down."
• "When the plunger is released, Spring 1 expands, which pulls Rod 1 back (remember that the distance can be no more than one unit)."
• "The maximum distance between Rod 1 and the plunger is fixed by means of a stop (not shown), so that the plunger can push against Spring 2 which pushes against Rod 1, but Spring 2 cannot push Rod 1 unless the plunger is pushed."