The uncool, cool kind of threesome in which a male inserts a double donger in his ass, and has sex with two women with both the forward and backward motion of his hips.
Oh man I totally murtained your mom and sister last night.
by Twomack July 28, 2009
A shortened version of "meat curtains"
Damn, Debbie needs bigger undiez, her murtains are hanging out.
by JAHY45 August 20, 2007