/ Dictionary / Index M mesopeak: Meaning and Definition of Find definitions for: mes•o•peak Pronunciation: (mez'u-pēk", mes'-, mē'zu-, -su-), [key] — n. the level of maximum temperature in the mesophere, at an altitude of about 30 mi. (48 km). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mesopause mesopelagic 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