any march that is longer than troops are accustomed to and maintained at a faster pace than usual, generally undertaken for a particular objective under emergency conditions.
Origin of forced march
First recorded in 1760–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for forced march
military a march in which normal needs are subordinated to the need for speed
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