Definition: The word acetnaphthalide is a chemical compound derived from a group of natural products, specifically a particular type of phytolacca tree (Diospyros melanoxylon). The term "ace" refers to the presence of an acidic substance that breaks down and dissolves in water. "Tla" refers to the presence of an alkaline substance that binds to molecules and strengthens them, while "phth" means the presence of a phenol group.