defense mechanism: Meaning and Definition of

defense' mech"anism

Pronunciation: [key]
  1. the defensive reaction of an organism, as against a pathogenic microorganism.
  2. an unconscious process, as denial, that protects an individual from unacceptable or painful ideas or impulses.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.