cou·ma·rin  (kōō'mər-ĭn)  n. A fragrant crystalline compound, C9H6O2, extracted from several plants, such as tonka beans and sweet clover, or produced synthetically and widely used in perfumes. [French coumarine, from coumarou, tonka bean tree, from Spanish coumarú, from Portuguese cumaru, from Tupi cumarú, commaru.] cou'ma·ric (-mər-ĭk) adj. |