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