One of a number of a class of sphingolipids, N-acyl derivatives with long chains. Ceramide is the core molecule for the synthesis of sphingomyelin, an essential lipid for myelination and neurotransmission; it may function as a second messenger to stimulate differentiation, inhibit proliferation, and induce apoptosis. Check for active clinical trialsusing this agent. or An antibiotic drug that belongs to the family of drugs called cephalosporins.