bunflapper 

An extraordinarily loud and resonant release of gas.

Was that a big diesel rig downshifting on the highway or did grampa just shit his Depends?

bunflapper by Leon Sphincts August 29, 2003

BumFapper

Bum - The obvious, ass, fanny (If you're american)

Fapper - Tossing off
BumFapper
Do the maths

Avalon Audrey: "Wow Chelly, isn't Jonjo the biggest bumfapper you've ever seen in your life?"

Chelsey Amelia: "He is indeed Avie!"

BumFapper by bumfappers annonymous August 2, 2009

Funflapper 

A woman's breast or tit.

This chick was on top of me yesterday and her funflappers were bouncing off my face.

Funflapper by shamus mcfly February 17, 2010