from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The integrated system of organs involved in the intake and exchange of oxygen and carbon dioxide between an organism and the environment.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The system of organs serving for respiration.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the system for taking in oxygen and giving off carbon dioxide; in terrestrial animals this is accomplished by breathing
Sorry, no etymologies found.