(thing) by danlowlite Tue Oct 17 2000 at 20:57:12
This is a large, triangular (neck to scapula to the small of the back) muscle in your back, it helps to rotate, retract, and elevate the scapula. If the scapula, for some reason, is stuck somehow, it extends and laterally flexes the neck.

The Human Anatomy

I like it!