/ Dictionary / Index M minor planet: Meaning and Definition of Find definitions for: mi'nor plan'et Pronunciation: [key] asteroid (def. 1). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. minor piece minor premise Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language