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definitions

set width

noun Printing.

(in automatic typesetting) the width measured by the lowercase alphabet of a particular size and font of type.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for set width

set width

noun

another name for set 1 (def. 39)
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