- psychol any stimulus evoking an unlearnt response, esp in the context of classical conditioning, in which the conditioned stimulus is followed by the unconditioned one
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
- A stimulus that elicits an unconditioned response; for example, food is an unconditioned stimulus for a hungry animal, and salivation is the unconditioned response.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.