Coumadin n.

by 1953, name for human anti-coagulant use of the rat poison warfarin sodium, abstracted from the chemical name, 3-(α-acetonylbenzyl)-4-hydroxycoumarin; earlier known as Dicoumarol, it attained publicity when it was used in 1955 to treat U.S. President Dwight Eisenhower after a heart attack. Coumarin as the name of an aromatic crystalline substance is by 1830 in English, from French coumarine, from coumarou, the native name in Guyana of the tonka or tonquin bean, one source of the substance.