Pimped out pants that contain a whole array of speakers, amplifiers, and subwoofers. A party in the pants.
Jack turned up the bass on his jam pants to feel the good vibrations.
by Garrix September 17, 2005
jam pants refers to the slight stain left on girls pants when they are on their period.
"look at thats girls jam pants"
by blondie! April 22, 2009