1. a. The act or process of inhaling and exhaling; breathing. b. The act or process
by which an organism without lungs, such as a fish or plant, exchanges gases with
its environment.
2. a. The oxidative process occurring within living
cells by which the chemical energy of organic molecules is released in a series
of metabolic steps involving the consumption of oxygen
and the liberation of carbon dioxide and water. b. Any of various analogous
metabolic processes by which certain organisms, such
as fungi and anaerobic bacteria, obtain energy from
organic molecules.
Excerpted from The American Heritage Dictionary of the English Language, Third
Edition Copyright © 1992 by Houghton Mifflin Company. Electronic version
licensed from Lernout & Hauspie Speech Products N.V., further reproduction
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