Horehound

n. [ OE. horehune, AS. hārhune; hār hoar, gray + hune horehound; cf. L. cunila a species of organum, Gr. &unr_;, Skr. kn&unr_;y to smell. ] (Bot.) 1. A plant of the genus Marrubium (Marrubium vulgare), which has a bitter taste, and is a weak tonic, used as a household remedy for colds, coughing, etc. [ Written also hoarhound. ] [ 1913 Webster ]

2. A lozenge or tablet, usually sweetened, containing extract of horehound, used as a remedy for a cough or a sore throat. [ PJC ]

Fetid horehound, or
Black horehound, a disagreeable plant resembling horehound (Ballota nigra). --
Water horehound, a species of the genus Lycopus, resembling mint, but not aromatic. [ 1913 Webster ]