Montgolfier Syllabification: (Mont·gol·fi·er)Pronunciation: /mäntˈgälfēər, môNgôlˈfyā/Definition of Montgolfier family name of brothers Joseph Michel (1740–1810) and Jacques Étienne (1745–99), French inventors and pioneers in hot-air ballooning. Montgolfier in other Oxford dictionaries Definition of Montgolfier in the British & World English dictionary