/ Dictionary / Index M mesogastrium: Meaning and Definition of Find definitions for: mes•o•gas•tri•um Pronunciation: (mez"u-gas'trē-um, mes"-, mē"zu-, -su-), [key] — pl. -tri•a the mesentery of the embryonic stomach. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mesodontism mesoglea Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language