Origin of mound builder
First recorded in 1835–45
a member of one of the various American Indian tribes who, in prehistoric and early historic times, erected the burial mounds and other earthworks of the Mississippi drainage basin and southeastern U.S.
Origin of Mound Builder
An Americanism dating back to 1830–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a member of a group of prehistoric inhabitants of the Mississippi region who built altar-mounds, tumuli, etc
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