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definitions

-tropic

  1. a combining form with the meanings “turned toward, with an orientation toward” that specified by the initial element (geotropic), “having an affinity for, affecting” what is specified (lipotropic; neurotropic; psychotropic), “affecting the activity of, maintaining” a specified organ (gonadotropic).
Compare -trophic.

Origin of -tropic

see origin at tropic
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for -tropic

-tropic

adj combining form
  1. turning or developing in response to a certain stimulusheliotropic

Word Origin for -tropic

from Greek tropos a turn; see trope
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
-tropic in Medicine

-tropic

suff.
  1. Affecting or attracted to something specified:gonadotropic.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.