n.
The turning or bending movement of an organism or a part toward or away from an external stimulus, such as light, heat, or gravity.
[From -TROPISM.]
tropic tro'pic or tro·pis'tic adj.tropistically tro·pis'ti·cal·ly adv.
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.
