The UnderGround 

Also called the UG. A message board forum for MMA (Mixed Martial Arts) fans and fighters. Members often refer to themselves as UG'ers. Contains many UFC and PrideFC elitists/nuthuggers that hate TUF noobs(new fans due to The Ultimate Fighter Reality show). Members tend to belittle others for liking certian fighters, or for not knowing who certain figters are.
There are different levels of access to the forum, a free or MUDNAMER account and a Pro account(blue, green, red name)which costs $$.
Mudmaners usually get shit on by the Pro UG'ers for not buying a name (forum namism if ya ask me).

Ban this mudnamer, The UnderGround doesnt need anymore TUF noobs.

The UnderGround by Curtious Reach Around Naked Choke February 21, 2007

The Underground Railroad 

A legion of anal driven women using horse cock size strap-ons as means of their sexual intercourse, form a circle of consecutive anal penetration. It is at this point that each member donkey punches the participant in front of them forcing defication. Said feces is then tossed gently and accurately into the center of the circle where a concetric circle of outward facing males who are in fact beating off vigorously, racing each other for their nut. The loser's punishment is to crawl through a tunnel made by the legs of the participants while they each take turns shitting on him. *note that the loser has to crawl slowly and with their back to the floor, and mouth open wide.*

-"Hey, since we have nothing else to do today 20 horse cock strap-ons, wanna take a ride on the secret The Underground Railroad today?"
-"Yeah man, that sounds great, just don't let any weirdos in this time!"

The Underground Railroad by Charlie Octopus September 20, 2013

the underground railroad 

when a girl starts sucking on your balls, then licks your gooch, and finishes it off with a rimjob. It's a funny experience that feels great, but is secretive just like the real underground railroad from back in the day.

So last night this slam piece was sucking my dick when all of the sudden she gave me the underground railroad

the underground railroad by rocklobster 69 October 4, 2011

The Underground Sound 

(1) A newspaper created in a heroic effort to take over the world and set that shit free. Composed of a staff of clever, witty, intellegent, and attractive high school students who are just pawns in their super hot editor's pathetic attempt to dictate society to a world similar to the pokemon mindset. This basically encompasses the ideals of using words and editorials to attack and defend anything and everything our trainers stand for.

(2) The ultimate union of aesthetics and phonetics, merged together into a cheap looking magazine-style representation of LIFE.

THE UNDERGROUND SOUND OWNS YOU.

the end.

Taylor: pikachu, i choose you!
George Bush: aw, not another editorial.
Taylor: pikachu, thunderbolt, now!
George Bush: damnit, i'm front page.
Taylor: pikachu, return!
George Bush: I hate you, The Underground Sound.

The Underground Sound by taylor is awesome October 17, 2006

the underground railroad 

The toilet and/or the entire human fecal system.

Called the underground railroad because "black shit escapes."

Goddamnit, I better go visit the underground railroad.

the underground railroad by sal May 18, 2004

The Underground Camman 

A sexual intercourse position in which one partner grabs the other firmly, lifting them up while they put their legs upon the shoulders of the first partner. During this, the first partner will penetrate the second partner's orifice while screaming 'It's time for the Underground Camman".

"Bro I took this chick home last night and gave her the Underground Camman"

The Underground Camman by MelonMan42 August 10, 2021

taking the underground railroad 

When someone snorts cocaine with a harriet tubman 20$ bill

Guy: "hey man you wanna be taking the underground railroad cuz my dealer got me the good hook up"

taking the underground railroad by GuccimaestroSS June 2, 2016