The Collaborative International Dictionary of English v.0.48:
Anatropal \A*nat"ro*pal\, Anatropous \A*nat"ro*pous\, a. [Gr. ? up + ? to turn.] (Bot.) Having the ovule inverted at an early period in its development, so that the chalaza is as the apparent apex; -- opposed to orthotropous. --Gray. [1913 Webster]