Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
double-spacing is a noun meaning "typing that leaves alternate lines blank". It carries one recorded sense.
typing that leaves alternate lines blank
Definitions, synonyms and semantic relations for double-spacing come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.