coumarin
cou·ma·rin
noun \ˈkü-mə-rən\Definition of COUMARIN
: a toxic white crystalline lactone C9H6O2 with an odor of new-mown hay found in plants or made synthetically and used especially in perfumery and as the parent compound in various anticoagulant agents (as warfarin); also : a derivative of this compound
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