/ Dictionary / Index M mesophile: Meaning and Definition of Find definitions for: mes•o•phile Pronunciation: (mez'u-fīl", -fil, mes'-, mē'zu-, -su-), [key] — Bacteriol. Bacteriol. —adj. mesophilic. —n. a mesophilic bacterium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mesopelagic mesophilic Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language