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