Tumersault 

The feeling in the pit of your stomach when on a roller coaster or drop ride.

That roller coaster was crazy, my stomach was doing mad tumersaults!

Tumersault by Thinkers February 2, 2019

Tumbersault 

A running dive into a summersault, or forward roll. May also be completed rolling sideways on ones back.

The boy was seen doing a tumbersault in the middle of the road to escape the police.

Tumbersault by ioinfodinfd February 28, 2010

Cumersault 

When you sonic the hedgehog your way through a trail of ejaculate.

“Oh no! My spinal region is awfully sticky from that cumersault.”

Cumersault by Walt_Disney May 4, 2021

tumbersaulting 

A confusing and dizzying combination of tumbling and somersaulting while one is in mid air, usually a result of a botched high dive.

"Those guys look ridiculous, tumbersaulting through the air like that"

tumbersaulting by steve8311 May 26, 2009