What is "cardenolide"

n. (context organic chemistry English) Any of many steroid lactones present in plants as glycosides; they are all toxic, affecting the heart

Cardenolide is a type of steroid. Many plants contain derivatives, collectively known as cardenolides, including many in the form of cardenolide glycosides (cardenolides that contain structural groups derived from sugars). Cardenolide glycosides are often toxic; specifically, they are heart-arresting.