'space bar' definitions:

Definition of 'space bar'

noun

The bar-shaped typewriter key that introduces spaces when used

Definition of 'space bar'

From: GCIDE

space bar \space bar\ or space key \space key\ (Mach., Computers) A bar or key, in a typewriter, typesetting machine, or other keyboard (as a computer keyboard), used to insert a space between letters. [Webster 1913 Suppl. +PJC]

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