Noun
the male gametophyte produced by a microspore
Source: WordNetIn seed plants, the microgametophyte (pollen grain) travels to the vicinity of the egg cell (carried by a physical or animal vector), and produces two sperm by mitosis. Source: Internet
The egg producing gametophyte is known as a megagametophyte, because it is typically larger, and the sperm producing gametophyte is known as a microgametophyte. Source: Internet