pediplain (ped'-i-plain). A term proposed by Maxson and Anderson (1935, p.94) for an extensive thinly alluviated erosion surface formed in a desert region by the coalescence of two or more adjacent pediments and occasional desert domes, and representing the end result (the "peneplain") of the mature stage of the arid erosion cycle. Howard (1942) objected to the term because the surface to which it is applied is not wholly at the base of a slope and is not a "plain" in the true geomorphic sense. Cf: pediplane; coalescing pediment. Syn: panfan; desert peneplain; desert plain.