Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
foul-spoken is an adjective meaning "using foul or obscene language". It carries one recorded sense.
using foul or obscene language
“noisy foul-mouthed women all shouting at once”
Definitions, synonyms and semantic relations for foul-spoken come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.