Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
do-nothing is a noun and adjective meaning "person who does no work". It carries 2 recorded senses.
person who does no work
“a lazy bum”
characterized by inability or unwillingness to work toward a goal or assume responsibility
“a do-nothing government”
Definitions, synonyms and semantic relations for do-nothing come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.