carmustine /kärmus″tin/ , a lipid-soluble nitrosourea, 1, 3-bis (2-chloroethyl)-l-nitrosourea, used as a single antineoplastic agent or with other approved chemotherapeutic agents in the treatment of brain tumors, multiple myeloma, Hodgkin’s disease, and non-Hodgkin’s lymphomas. Also called BCNU.