Merriam-Webster Collegiate Dictionary - digitalis

 noun  Etymology: New Latin, genus name, from Latin, of a finger, from digitus; from its finger-shaped corolla  Date: 1664  1. foxglove  2. the dried powdered leaf of the common foxglove that contains glycosides which act on the heart and that is a powerful cardiotonic serving especially to increase the force of myocardial contraction; broadly any of various cardiac glycosides (as digitalin or digoxin) that are constituents of ~ or are derived from a related foxglove (Digitalis lanata)