Erythrolysin is a term that describes a bacterial toxin that specifically lyses (destroys) red blood cells. There are a number of different terms that could be considered synonyms for erythrolysin, depending on the context in which the term is being used. For example, haemolysin is a more general term that refers to any substance that destroys red blood cells, while the term hemolysin is used specifically to describe a substance that breaks down hemoglobin within red blood cells. Other terms that could be used to describe erythrolysin include red blood cell lytic factor, erythrotoxin, or simply RBC lytic toxin.