Cardenolides are a type of steroids. Many plants contain cardenolides in the form of cardenolide glycosides (for example cardenolides that contain structural groups derived from sugars; see Glycoside). Cardenolides are toxic (specifically, heart-arresting). Etymology Supposedly, the term derives from Greek kardiā, heart. It shouldn't be confused with cardanolides. Cardanolides are a class of steroids (or aglycones if viewed as cardiac glycoside constituents), and cardenolides are a subtyp… (More on Cardenolide)