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definitions

soft drug

noun
  1. a drug, usually illicit, that does not produce significant psychological or physical dependence.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
soft drug in Medicine

soft drug

n.
  1. A drug considered to be nonaddictive and less damaging to the health than a hard drug.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.