Syllable division and stress derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
inaccessibly is an adverb meaning "in an inaccessible manner". It carries one recorded sense.
in an inaccessible manner
“located inaccessibly on the top of a mountain”
Definitions, synonyms and semantic relations for inaccessibly come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.