'Microspore' definitions:
Definition of 'microspore'
(from WordNet)
noun
Smaller of the two types of spore produced in heterosporous plants; develops in the pollen sac into a male gametophyte
Definition of 'Microspore'
From: GCIDE
- Microspore \Mi"cro*spore\ (m[imac]"kr[-o]*sp[=o]r), n. [Micro- + spore.] (Bot.) One of the exceedingly minute spores found in certain flowerless plants, as Selaginella and Isoetes, which bear two kinds of spores, one very much smaller than the other. Cf. Macrospore. [1913 Webster]