- the smaller of the two kinds of spores characteristically produced by seed plants and some fern allies, developing into a male gametophyte.Compare megaspore,
- a pollen grain.
- the smaller of two types of spore produced by some spore-bearing plants, which develops into the male gametophyteCompare megaspore (def. 1)
- the pollen grain of seed plants
n.1856, from micro- + spore.
- One of the two types of haploid spores produced by a heterosporous plant. Microspores develop into male gametophytes and are usually smaller than megaspores. In angiosperms, the microspore develops into the pollen grain.