In biology|lang=en terms the difference between protandry and protogynous
is that
protandry is (biology) the condition in which an organism begins life as a male and then changes into a female while
protogynous is (biology) exhibiting protogyny.
In botany|lang=en terms the difference between protandry and protogynous
is that
protandry is (botany) the condition of flowers whose male parts mature before the female ones while
protogynous is (botany) whose female parts (archegonia]]) mature before the male parts ([[antheridium|antheridia) release their spermatozoids.
As a noun protandry
is (biology) the condition in which an organism begins life as a male and then changes into a female.
As an adjective protogynous is
(biology) exhibiting protogyny.