nicotinamide Syllabification: (nic·o·tin·a·mide)Pronunciation: /ˌnikəˈtinəˌmīd, -ˈtēn-/Definition of nicotinamide noun Biochemistry a compound that is the form in which nicotinic acid often occurs in nature. The amide of nicotinic acid; chemical formula: (C5H4N)CONH2 nicotinamide in other Oxford dictionaries Definition of nicotinamide in the British & World English dictionary