1. The process of nourishing or being nourished, especially the process by which a living organism assimilates food and uses it for growth and for replacement of tissues.
2. The science or study that deals with food and nourishment, especially in humans.
3. A source of nourishment; food.

[Middle English nutricion, from Old French nutrition, from Late Latin nūtrītiō, nūtrītiōn-, from Latin nūtrītus, past participle of nūtrīre, to suckle.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.