digitalis
noun(dig-i-tal-is)
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 (such as digitalin or digoxin) that are constituents of digitalis or are derived from a related foxglove (Digitalis lanata)