multivibrator Syllabification: (mul·ti·vi·bra·tor)Pronunciation: /ˌməltiˈvīˌbrātər/Definition of multivibrator noun Electronics a device consisting of two amplifying transistors or valves, each with its output connected to the input of the other, producing an oscillatory signal. multivibrator in other Oxford dictionaries Definition of multivibrator in the British & World English dictionary