er·y·thro·i·dine \ˌerəˈthrōəˌdēn, -ōədən\noun (-s) Etymology:erythr- + -idine : a crystalline alkaloid C16H19NO3 obtained from plants of the genus Erythrina as a mixture of stereoisomers; especially: the beta stereoisomer that has curariform activity and is a depressant of the central nervous system