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military pace

noun
  1. a pace, equal to a single step, used to coordinate the marching of soldiers, equal in the U.S. to 2½ feet (76 cm) for quick time and 3 feet (91 cm) for double time.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for military pace

military pace

noun
  1. the pace of a single step in marching, taken to be 30 inches for quick time (120 paces to the minute) in both the British and US armies
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