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choropleth

noun

  1. a symbol or marked and bounded area on a map denoting the distribution of some property
  2. (as modifier)a choropleth map

Word Origin for choropleth

C20: from Gk khōra place + plēthos multitude
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