Pronunciation: (dub'ul spās'), [key]
—v., -spaced, -spac•ing.
to type (text, copy, etc.) leaving a full space between lines: Always double-space a term paper.
to type leaving a full space between lines: I can never remember to double-space.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.