Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
messily is an adverb meaning "in a messy, untidy manner". It carries one recorded sense.
in a messy, untidy manner
“Rossi spat very deliberately, and very messily, upon Durieux's party card”
Definitions, synonyms and semantic relations for messily come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.