the larger of the two kinds of spores characteristically produced by seed plants and a few fern allies, developing into a female gametophyte. Compare microspore.
meg·a·spore (měg'ə-spôr', -spōr') n. The larger of two types of spores that give rise to a female gametophyte. Also called macrospore. meg'a·spor'ic adj.
Main Entry: mega·spore Pronunciation: 'meg-&-"spO(&)r, -"spo(&)r Function: noun 1: a spore in heterosporous plants that givesrise to female gametophytes and is generally larger than a microspore 2:MACROSPORE —mega·spor·ic/"meg-&-'spOr-ik, -'spor-/adjective