a route used during the U.S. westward migrations, especially in the period from 1840 to 1860, starting in Missouri and ending in Oregon. About 2000 miles (3200 km) long.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
an early pioneering route across the central US, from Independence, W Missouri, to the Columbia River country of N Oregon: used chiefly between 1804 and 1860. Length: about 3220 km (2000 miles)
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
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