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planosol

British  
/ ˈpleɪnəˌsɒl /

noun

  1. a type of intrazonal soil of humid or subhumid uplands having a strongly leached upper layer overlying a clay hardpan

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of planosol

C20: from Latin plano- + solum soil