n. [ Gr. 'eryqro`s red. ] 1. (Chem.) A colorless crystalline substance, C4H6.(OH)4, of a sweet, cooling taste, extracted from certain lichens, and obtained by the decomposition of erythrin; -- called also erythrol, erythroglucin, erythromannite, pseudorcin, cobalt bloom, and under the name phycite obtained from the alga Protococcus vulgaris. It is a tetrabasic alcohol, corresponding to glycol and glycerin. [ 1913 Webster ]

2. (Min.) A rose-red mineral, crystallized and earthy, a hydrous arseniate of cobalt, known also as cobalt bloom; -- called also erythrin or erythrine. [ 1913 Webster ]