Roland's definitions
One definition comes from the Roller Derby when the fastest skater passes those on the other team. When the skater is going really fast he is on a JAM. A slang useage example would be "let's jam".
by Roland November 13, 2005
Get the jammug. A "safe" hideout to meet & split the cash after a heist, or a place to live when you want to drop out of sight
by roland November 11, 2004
Get the crash-pad or crashpadmug.