acetobacter Syllabification: (a·ce·to·bac·ter)Pronunciation: /əˌsētəˈbaktər, ˌasitə-/Definition of acetobacter noun bacteria that oxidize organic compounds to acetic acid, as in vinegar formation. Genus Acetobacter; Gram-negative oval or rod-shaped bacteria Origin:modern Latin (genus name), from aceto- + bacteriumacetobacter in other Oxford dictionaries Definition of acetobacter in the British & World English dictionary