horehound

noun

• a strong-smelling hairy plant of the mint family, with a tradition of use in medicine.

  • Two species in the family Labiatae: white horehound (Marrubium vulgare) and black horehound (Ballota nigra), a Eurasian plant which was formerly said to cure the bite of a mad dog
• [mass noun] the bitter aromatic juice of white horehound, used especially in the treatment of coughs and colds.