from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The system of cells, tissues, and organs that regulates the body's responses to internal and external stimuli. In vertebrates it consists of the brain, spinal cord, nerves, ganglia, and parts of the receptor and effector organs.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An organ system that coordinates the activities of muscles, monitors organs, constructs and processes data received from the senses, and initiates actions.
from the GNU version of the Collaborative International Dictionary of English
- adj. the specialized coördinating apparatus which endows animals with sensation and volition. In vertebrates it is often divided into three systems: the central, brain and spinal cord; the peripheral, cranial and spinal nerves; and the sympathetic. See Brain, Nerve, Spinal cord, under Spinal, and Sympathetic system, under Sympathetic, and Illust. in Appendix.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the sensory and control apparatus consisting of a network of nerve cells
Sorry, no etymologies found.