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definitions

grid reference

noun
  1. a method of locating a point on a map or plan by a number referring to the lines of a grid drawn upon the map or plan and to subdivisions of the space between the lines
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