accessory nerve

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Either of the 11th pair of cranial nerves, which convey motor impulses to the pharynx and muscles of the upper thorax, back, and shoulders.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun medicine, physiology The 11th cranial nerves of higher vertebrates, controlling the pharynx, and the muscles of the upper chest and shoulders.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun arises from two sets of roots (cranial and spinal) that unite to form the nerve