Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
undefinable is an adjective meaning "not capable of being precisely or readily described; not easily put into words". It carries one recorded sense.
not capable of being precisely or readily described; not easily put into words
“an indefinable feeling of terror”
“an abstract concept that seems indefinable”
Definitions, synonyms and semantic relations for undefinable come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.