Bumper Butts 

A game played while on the bus whereby two (or more) people repeatedly touch butts (tap ass, moon landing, etc).

"Wow that was an exhilterating game of bumper butts! I feel like I owe you a drink!"

Bumper Butts by gjcourt November 9, 2012

Bumper butt 

It's a butt that is is very big and attractive were you wanna hit it. Like in bumper cars you wanna hit the other people.

My boyfriend has a bumper butt

Bumper butt by Gpnfa July 10, 2014

Butt Bumper 

A Butt Bumper is a guy that screws around. He is a bumper of butts, Also used to describe a gay guy. Like hey look at the Butt Bumper over there talking to his boy friend, Butt Bumper. Also meaning a person that procrastinates Example hey dude you need to hire someone else this dude is a serious Butt Bumper. Also A Butt Head

Butt Bumper,

Butt Bumper by Daman Money January 25, 2010

Bummer Butt 

People on the beach who when you see from behind can ruin your day because there swimsuits and butts are the wrong size for each other.

I was having a good time relaxing at the beach until I saw a bummer butt and had to go home.

Bummer Butt by Bullshitzer June 11, 2010