Theobromine \The`o*bro"mine\, n. (Chem.) An alkaloidal ureide, {C7H8N4O2}, homologous with and resembling caffeine, produced artificially, and also extracted from cacao and chocolate (from {Theobroma Cacao}) as a bitter white crystalline substance; -- called also {dimethyl xanthine}. [1913 Webster]