scalene muscle

[skālēn′, skā-lēn]
n.
  1. Any of three muscles on each side of the neck that serve to bend and rotate the neck and that assist breathing by raising or fixing the first two ribs.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.