- regmaA kind of dry fruit, consisting of three or more cells, each of which eventually breaks open at the inner angle.
- regmacarpA fruit which, when mature, splits open to release its seeds; a dehiscent fruit.
- regmaglyptA small, shallow indentation or pit on the surface of a meteorite, resembling a thumbprint impression in clay, created by ablation while falling in an atmosphere.
- rhegmaA rupture or fracture.