circulatory system

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

• noun The system of structures in vertebrates consisting of the heart, blood vessels, and lymphatics, by which blood and lymph are circulated throughout the body.
• noun A similar system by which a fluid, such as hemolymph, is distributed in other animals.

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

• noun physiology The parts of a animal body comprising the heart, veins, capillaries and arteries.
• noun The parts of a machine responsible for the circulation of some fluid.

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

• noun the organs and tissues involved in circulating blood and lymph through the body