Pronunciation: (bit'urz),[key] —n.(used with a pl. v.) 1. a liquid, often an alcoholic liquor, in which bitter herbs or roots have steeped, used as a flavoring, esp. in mixed drinks, or as a tonic.
2. Pharm. a. a liquid, usually alcoholic, impregnated with a bitter medicine, as gentian or quassia, used to increase the appetite or as a tonic.
b. bitter medicinal substances in general, as quinine.