Haemolysin

Part of speech: noun

Definitions

1. A toxin or enzyme produced by certain bacteria that breaks down the membrane of red blood cells and causes them to rupture
2. Any agent, typically a bacterial product, that damages or destroys erythrocytes by rupturing their cell membranes
3. A substance released by microorganisms that dissolves red blood cells and releases their hemoglobin into the surrounding fluid

Etymology: Haemolysin is a compound built from two Greek-derived pieces, and its first half carries a surprisingly old word for blood. The Ancient Greek "haîmă" (blood) gave rise to the combining form "haimo-", which passed into English as "haemo-" (or "hemo-" in American spelling). The second half, "-lysin", is a modern scientific suffix formed from "lysis", a Greek noun meaning "loosening" or "dissolution", with "-in" added as the chemical ending that English uses for protein-like substances. Put together, the word describes a substance that breaks down red blood cells. The term is a technical coinage from the modern scientific vocabulary of the 19th and 20th centuries, when researchers needed names for newly identified toxins and agents. It was not used by the ancient Greeks, who had the building blocks but not the concept of a chemical that dissolves blood cells.

Synonyms: hemolysin