/ Dictionary / Index M main stem: Meaning and Definition of Find definitions for: main' stem' Pronunciation: [key] the main street of a city or town; the main drag. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mainstay main storage Related Content Daily Word Quiz: philtrum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language