Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
strung-out is an adjective meaning "addicted to a drug". It carries one recorded sense.
addicted to a drug
Definitions, synonyms and semantic relations for strung-out come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.