flatcest 

The act of having sex with your flatmate, even though you know this may be inadvisable given that you have to live together afterwards.

"I walked into Rachael's room and she was in bed with John! They totally committed flatcest last night!"

flatcest by possessed July 23, 2007

fratcest 

(Noun): When two or more members of the same fraternity (usually co-ed) have a steamy sexual encounter.

Adjective form: fratcestual

Girl 1: Ho, I saw you giving our frat bro a frat job at the party last night. Did you two hookup??

Girl 2: Chill, beezie, ain't nothin' wrong with a little fratcest.

fratcest by Allpods October 19, 2010

flatchested 

the name for a person with a very flat chest. usually very offending to most girls who have no boobs.

A: ew. look at that tiffany girls myspace picture.
B: i know. no one wannts to see her in a bathing suit.
A: and shes pressing her arms together ro make it look like she has boobs.
A: she is so flatchested.

flatchested by Alexa H August 24, 2006