A Slooty Nickel is a term reffering to a girl who is both slutty, and a 5 on a scale of 1-10. The Slooty Nickel is a girl who is the "might as well girl" at the end of the night.
JON: Hey man, I'm going to hook up with that slooty nickel.
DAVE:Why?
JON:Because no good looking girl here is going to put out. And why not?