ni Nheengatu • niacin · · · Info · Definitions · Synonyms · Characters · · ni · · Text Latin · · Script 2 · · Length Definitions · · · (noun) a hard malleable ductile silvery metallic element that is resistant to corrosion; used in alloys; occurs in pentlandite and smaltite and garnierite and millerite. Synonyms: nickel, Ni, atomic number 28. · · Noun Definition 1 Synonyms · · · nickel · · Synonym 1 atomic number 28 · · Synonym 2 Characters · · i latin small letter i U+0069 n latin small letter n U+006E