Baby on a trampoline 

The act of pulling taught the scrotum in the "batwing" fashion and continuing to bounce one's flaccid small penis of said flap, thus creating the image of a baby jumping on a trampoline.

Hey....you ever seen a baby on a trampoline?
(pulls scrotum taught and bounces dingaling off it repeatedly) *everyone screams and gives a look of disgust...then they laugh.

Baby on a trampoline by DocCod November 6, 2015

pink trampoline 

A pink trampoline is the way someone's asshole looks. Think about it...

Wow! That asshole of yours looks like a pink trampoline! Pink and a bouncy.

pink trampoline by trampoline enthusiast April 24, 2017

bald headed mouse on a trampoline 

stretching one's scrotum forward and shaking it up and down so that the tip of the penis bounces on it

hey stuart, did you ever see a bald headed mouse on a trampoline?

bald headed mouse on a trampoline by madfunfrank September 30, 2013

areola trampoline 

Used to describe a woman's very large areolas. They are big enough to jump on like a trampoline.

Last night I jumped around on her areola trampolines.

areola trampoline by Mossytwat October 6, 2008

Squirrel on a Trampoline 

The act of spreading your scrotum to form a flat surface like a Trampoline and then bouncing your flacid penis like a squirrel bouncing on a trampoline.

At the party Jimbo surprised everyone by pulling out the Squirrel on a Trampoline trick and .

Squirrel on a Trampoline by Haught Carl December 20, 2009

alaskan trampoline

A sex move, in which a man throws a woman on edge of the bed and thrust his penis in her vagina whilst motorboating her tits.

She had such huge tits I couldn't stop my self from giving her an "alaskan trampoline".

alaskan trampoline by AlaskanMan June 8, 2016

Waistband Trampoline 

A technique used by men to remove excess pee from their penis after urinating in a urinal. The male bounces his penis up and down on his waistband a few times before he zips up, preventing underwear dribble.

I bounced my dick on my waistband trampoline a few times before leaving the urinal so I wouldn’t get piss pants.

Waistband Trampoline by Brandon2k9 February 9, 2018