/ Dictionary / Index E experimental psychology: Meaning and Definition of Find definitions for: experimen'tal psychol'ogy Pronunciation: [key] the branch of psychology dealing with the study of emotional and mental activity, as learning, in humans and other animals by means of experimental methods. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. experimentalism experimental theater Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language