From The Collaborative International Dictionary of English v.0.48 :
Space \Space\, v. t. [imp. & p. p. Spaced; p. pr. & vb. n.
Spacong.] [Cf. F. espacer. See Space, n.] (Print.)
To arrange or adjust the spaces in or between; as, to space
words, lines, or letters.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
spaced
adj 1: spaced apart [syn: separated, spaced]
2: arranged with spaces between; often used as a combining form;
"widely spaced eyes" [ant: unspaced]