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American Expeditionary Forces

plural noun
  1. troops sent to Europe by the U.S. Army during World War I. Abbreviation: A.E.F., AEF
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for american expeditionary forces

American Expeditionary Forces

pl n
  1. the troops sent to Europe by the US during World War I
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