Webster's Revised Unabridged Dictionary · 1913

Orthotropal

Orthotropal , adjective

[Ortho- + Greek {not transcribed} to turn: compare French orthotrope.]

(Botany) Having the axis of an ovule or seed straight from the hilum and chalaza to the orifice or the micropyle; atropous.

This word has also been used (but improperly) to describe any embryo whose radicle points towards, or is next to, the hilum.

Also: Orthotropous