Horehound

Part of speech: noun (n.)

A plant of the genus Marrubium (M. vulgare), which has a bitter taste, and is a weak tonic, used as a household remedy for colds, coughing, etc. [Written also hoarhound.] 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.