nicotinamide

This term refers to a specific chemical form of vitamin B3. In medical and scientific contexts, it is often used interchangeably with niacin, though nicotinamide is specifically the amide form of nicotinic acid. It is primarily discussed in the context of nutritional deficiencies, such as pellagra, or as a precursor to NAD+ in cellular metabolism.

As a chemical compound and a vitamin, the word is treated as an uncountable mass noun. It describes a substance rather than a discrete object, meaning it does not typically take a plural form in standard clinical or biochemical usage.