nerve impulse

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

• noun A wave of physical and chemical excitation along a nerve fiber in response to a stimulus, accompanied by a transient change in electric potential in the membrane of the fiber.

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

• noun physiology The signal transmitted along a nerve fibre, either in response to a stimulus (such as touch, pain or heat), or as an instruction (such as causing a muscle to contract).

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

• noun the electrical discharge that travels along a nerve fiber