mono Syllabification: (mon·o)Pronunciation: /ˈmänō/Translate mono | into German | into Italian | into Spanish Definition of mono adjective 1monophonic. 2monochrome. noun (plural monos) 1a monophonic recording. monophonic reproduction. 2a monochrome picture. monochrome reproduction. 3North Americanshort for infectious mononucleosis. 4North Americanshort for monofilament.mono in other Oxford dictionaries Definition of mono in the British & World English dictionary