/ Dictionary / Index D diet pill: Meaning and Definition of Find definitions for: di'et pill" Pronunciation: [key] a tablet or capsule containing chemical substances that aid in reducing or controlling body weight, usually by suppressing the appetite. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. diet kitchen Dietrich Related Content Daily Word Quiz: agitated Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language