[ meg-uh-spawr, -spohr ]
/ ˈmɛg əˌspɔr, -ˌspoʊr /

noun Botany.

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.
the embryo sac of a flowering plant.

Origin of megaspore

First recorded in 1885–90; mega- + spore
Also called macrospore.


meg·a·spor·ic [meg-uh-spawr-ik, -spor-] /ˌmɛg əˈspɔr ɪk, -ˈspɒr-/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for megaspore

British Dictionary definitions for megaspore

/ (ˈmɛɡəˌspɔː) /


Also called: macrospore the larger of the two types of spore produced by some spore-bearing plants, which develops into the female gametophyteCompare microspore (def. 1)
the cell in flowering plants that gives rise to the embryo sac

Derived forms of megaspore

megasporic, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for megaspore

[ mĕgə-spôr ]

One of the two types of haploid spores produced by a heterosporous plant. Megaspores develop into female gametophytes and are usually larger than microspores.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.