Definition of megaspore in English:



  • The larger of the two kinds of spores produced by some ferns.

    Compare with microspore
    • ‘They have male spores called microspores and female spores called megaspores.’
    • ‘Microfossil assemblages from rare black and grey clays in this succession contain only a variety of seeds, Microcarpolithes hexagonalis and megaspores, and there are neither foraminifera nor other marine microfossils.’
    • ‘Meiosis results in the production of four megaspores, containing half the number of chromosomes of the sporophyte.’
    • ‘Both of these genera are heterosporous, meaning that each species produces two distinctly different types of spores: microspores and megaspores.’
    • ‘Their heterosporous life cycle (including both megaspores and microspores) is likely to be an adaptation to their aquatic habit.’