Panic Plunge 

Phallic-looking ride at north Idaho's Silverwood theme park that locals refer to by many other impolite names.

Silverwood's Panic Plunge gives locals much to snicker about.

Panic Plunge by Disgruntled Idahoan August 5, 2007

Polar plunge

When you dip your fingers in ice then pull them out to put it right into a vagina

people about to have sex
Girl: babe want to go swimming in pussy?
Guy: hey lemme jump in!
Girl:Nah baby do the Polar Plunge!!
Guy: ALRIGHT!!

Polar plunge by JIIZZIINGFROG October 21, 2018

Final Plunge 

The state of a ship that is sinking (generally a large ship) where it is losing buoyancy and taking on water so fast that the ship starts to rapidly head downwards.

Typically, this stage in happens when water begins to reach the uppermost decks and the funnels, although it may differ from ship to ship because of certain circumstances and design of the watertight bulkheads. The Final Plunge is not over until the ship has sunk below the water line, usually not that long after the plunge began.

In shorter words, it is the beginning of the end for a ship’s service life due to reaching the point of no return when it comes to a drastic loss of buoyancy.

The Final Plunge of the R.M.S. Titanic occurred when the bow leaned so far downwards that water began spilling over the watertight bulkheads, and started to lap against the bridge and foward most funnel. Titanic would disappear beneath the waves 15-20 minutes after its final plunge began, with a total sinking time of ~2 hours and 40 minutes.

Final Plunge by Pét January 28, 2022

Timpani Cabbage Plunge 

Shortened to TCP
The act of defecating in someone's ear and then stiring it with your penis.

Charlie's a kinky bitch, he had a Timpani Cabbage Plunge last night
or
Charlie's a kinky bitch, he had TCP last night

Timpani Cabbage Plunge by Tired Squirrel April 17, 2009

maggot plunge 

When someone puts their unerect penis into the womens fajjwutti and it wiggles about like a maggot in water

Here comes the maggot plunge.

maggot plunge by Robert Lamb November 20, 2006

P-Town Plunge 

A sexual position wherein one person has sex with another person doggy style while periodically dunking their head in the water. Typically the water source is a toilet, and the person performing the P-Town Plunge uses their hand. Variations could include using a foot to do the dunking, or using a bucket or bathtub or other receptacle for the dunking...

Hank took that hooker into the bathroom in Vegas and did the P-Town Plunge on her.

P-Town Plunge by Micah2g January 6, 2008

Nestea Plunge 

Its an ionic Nestea commercial run in the 1980's and early 1990's where the actors drink Nestea drink. As the person begins to drink the tea they begin to experience a new reality, the ground around them turns into water. They are refreshed, full of both joy and tea, and begin to fall straight backwards into the water. This display of energy and emotion creates a desire for the fun-filled free fall. People nationwide reenacted the Nestea Plunge by falling backwards from a waters edge.

The Nestea Plunge is simply falling backwards into a pool.

Nestea Plunge by 1982 February 24, 2012