male sex organs maturing before the female ones, e.g. a flower shedding pollen before the stigma is receptive; cf. protogynous.
• (a.) Proterandrous.
describing a plant in which the release of pollen precedes and does not overlap the period of stigma receptivity (compare protogynous)
Having the male sex organs maturing before the female, of a flower, shedding the pollen before the stigma is receptive. ... Compare: protogynous. ... (09 Oct 1997) ... 
describing a plant in which the release of pollen precedes and does not overlap the period of stigma receptivity (compare protogynous)
Stamens shedding pollen before the stigma is receptive.
Pro·tan'drous adjective (Botany) Proterandrous. 
protandrous, protandry, protandric The condition of a hermaphrodite in which the male portion develops first or which is first male, and later sex reversed to female. 2. Said of a flower in which the pollen matures before the stigma is receptive.