1) The act of jiggling a clip on a bench back and forth just so, so that it may be able to come free. 2) Jason's mom.
"Jason your a fag, Shimmy Shamma"
by Cawk August 21, 2003
When you slowly wiggle a light clamp back and forth until it pops off the bench thing.
"Jason is a fag, shimmy shamma"
by Cawk August 20, 2003