/ Dictionary / Index M macrospore: Meaning and Definition of Find definitions for: mac•ro•spore Pronunciation: (mak'ru-spôr", -spōr"), [key] — n. Bot. megaspore. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: macrospore (Thesaurus) macrosporangium macrostructure Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language