| orthotropous; antitropous | -ออวุลตั้งตรง [พฤกษศาสตร์ ๑๘ ก.พ. ๒๕๔๕] |
| orthotropous | (adj) (of a plant ovule) completely straight with the micropyle at the apex, Ant. campylotropous |
| orthotropous ovule | (n) a completely straight ovule with the micropyle at the apex |
| Orthotropous | ☞ This word has also been used (but improperly) to describe any embryo whose radicle points towards, or is next to, the hilum. [ 1913 Webster ] Variants: Orthotropal |