Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
tranquilly is an adverb meaning "without emotional agitation". It carries one recorded sense.
without emotional agitation
“tranquilly she went on with her work”
Definitions, synonyms and semantic relations for tranquilly come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.