OrthotropalOr*thot"ro*pal\, Orthotropous \Or*thot"ro*pous\, a. [Ortho- + Gr. ? to turn: cf. F. orthotrope.] (Bot.) Having the axis of an ovule or seed straight from the hilum and chalaza to the orifice or the micropyle; atropous. Note: This word has also been used (but improperly) to describe any embryo whose radicle points towards, or is next to, the hilum.