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