Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
unionised is an adjective meaning "not converted into ions". It carries 2 recorded senses.
not converted into ions
Definitions, synonyms and semantic relations for unionised come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.