Cahokia Mounds

noun
  1. a group of very large prehistoric Indian earthworks in southwestern Illinois, consisting of mounds with flat tops that supported temples and other structures of mud and thatch.
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British Dictionary definitions for cahokia mounds

Cahokia Mounds

pl n
  1. the largest group of prehistoric Indian earthworks in the US, located northeast of East St Louis
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