the.com/digitalis

means A plant (foxglove) whose leaves yield a potent compound used medicinally to strengthen and regulate irregular heartbeats, though in excess it's a lethal poison.

from From Latin digitalis, meaning 'of the finger,' because the flower's tubular, tapering blossoms look like they were made to slip over a fingertip. German botanists had called it Fingerhut ('thimble') for the same reason, and the Latin name followed that logic when it was formally adopted for the genus in the 1500s. The medicinal use came later: an 18th-century English physician, William Withering, studied a folk remedy for dropsy (fluid buildup from heart failure) that turned out to contain foxglove, and he worked out through careful, patient-by-patient observation how to use it without killing people — effectively founding modern cardiac pharmacology on a cottage-garden poison.