gravitron 

A gravitron is the ride at those crappy city to city carnivals that spins real fast. It smells of vomit and sweat and features weight lifting benches on rollers along the wall. Your back is placed upon the bench with you in a semi standing position and the gravitron is activated. Once it reaches speed the benches slide up giving you the feeling of weightlessness. In actuality it is more the centrifugal/centripedal force that allows you to "stick" to the wall.

This guy i work with plans to buy a gravitron and travel the country as a carnie, but we were looking on usedrides.com and they're like $40,000 used!

gravitron by blake April 1, 2004

gravitron 

A "gravitron" is an all-glass gravity/vacuum pipe that is commonly used to smoke flavored tobacco and other legal substances.

I smoked out of a gravitron last night at my friend's place.

gravitron by Jon Evans May 27, 2006

gravitron 

n. a water-differential pipe crafted from an empty milk jug; gravity bong.

"after taking three hits out of the gravitron, i spent the rest of the night curled up next to the toilet.

gravitron by UberGanz August 19, 2008

Grasstronaut 

A person who is very high on marijuana.

Dude, I was so high last night.

You were a grasstronaut!

Grasstronaut by wizdog July 14, 2010

gravitowned 

The act of getting owned by gravity.

"That bitch fell right off that!
Yeah she got GRAVITOWNED!!!"

gravitowned by iNSANEKiLL3R July 20, 2007

Gravotron 

grav-uh-tron , When one takes an excessive ammount of gravol to feel hallucinagenic effects, they are known to be riding the Gravotron.

dude last night i was riding the gravotron and was tripping so hard

Gravotron by Josh Murphy March 30, 2008

Graviton

A hypothetical spin-2 massless boson which is responsible for the gravitational fields we experience everyday. The graviton is the quantum particle of gravity.

Particle colliders have yet to find a single graviton.

Graviton by A.froman September 3, 2010