di·rec·tion·al (dĭ-rĕk'shə-nəl, dī-)
adj.

1. Of or indicating direction: an automobile's directional lights.
2. Electronics. Capable of receiving or sending signals in one direction only.
3. Relating to guidance in effort, behavior, or thought: directional training.
4. Serving to point the future direction, as of fashion: "A directional group of sweater knit colors are winter pastels" (Women's Wear Daily).

n.
A directional signal.

directionality di·rec'tion·al'i·ty (-shə-năl'ĭ-tē) n.

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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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