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definitions

hair space

noun Printing.
  1. the thinnest metal space used to separate words, symbols, etc.

Origin of hair space

First recorded in 1835–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for hair space

hair space

noun
  1. printing the thinnest of the metal spaces used in setting type to separate letters or words
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