when an ovule is erect, with the micropyle directed away from the placenta; atropous; cf. amphitropous, anatropous, campylotropous.
• (a.) Having the axis of an ovule or seed straight from the hilum and chalaza to the orifice or the micropyle; atropous.
<cell biology> Of an ovule, erect so that the micropyle points away from the placenta. ... (09 Oct 1997) ... 
[adj] - (of a plant ovule) completely straight with the micropyle at the apex
adjective (of a plant ovule) completely straight with the micropyle at the apex
(of an ovule) straight and symmetrical, with the chalaza at the evident base and the micropyle at the opposite extremity.