func·tion·al (fŭngk'shə-nəl)
adj.

1. 1. Of or relating to a function.
   2. Of, relating to, or indicating a mathematical function or functions.
2. Designed for or adapted to a particular function or use: functional architecture.
3. Capable of performing; operative: a functional set of brakes.
4. Pathology. Involving functions rather than a physiological or structural cause.

n.
A linear function on vectors whose values are scalars.

functionally func'tion·al·ly adv.

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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.

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