A scarp on a planetary surface; pl.rupēs. The name, which means ‘cliff ’, is not a geological term but is used in the nomenclature of individual features, for example Rupes Recta (the Straight Wall) on the Moon and the Victoria Rupes on Mercury.
Geology and Earth Sciences
A term for a straight escarpment. The classic example is Rupes Recta, the ‘Straight Wall’ in Mare Nubium on the Moon.