Double Horizontal 

The act of two people having sex while laying down horizontally on to one another.

"I want to bust a double horizontal on yo ass."

Double Horizontal by Phi-boy April 24, 2003

Double Horizontal 

A Los Angeles based Electro/Ghetto Tech Duo whose first single "Honkahonk for Budonkadonk" was released this year.

I was at that Double Horizontal show when someone blew off that stink bomb and let that dirty basset hound run through the club and shake mud off on the throbbing dance floor full of people!

Double Horizontal by Willie Deez September 29, 2003