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single-space

American  
[sing-guhl-speys] / ˈsɪŋ gəlˈspeɪs /

verb (used with object)

single-spaced, single-spacing
  1. to type (copy) on each line space.


verb (used without object)

single-spaced, single-spacing
  1. to type copy leaving no blank spaces between lines.

single-space British  

verb

  1. (tr) to type (copy) without leaving a 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

Etymology

Origin of single-space

First recorded in 1935–40