white horehound; a genus of the gymnospermia order, belonging to the didynamia class of plants. There are nine species, the most remarkable of which is the vulgare, a native of Britain, growing naturally in waste places, and by way-sides near towns and villages, but not common. It has a strong and somewhat musky smell, and bitter taste. It is reputed attenuant and resolvent; an infusion of the leaves in water, sweetened with honey, is recommended in athematical and phthisical complaints, and most other diseases of the breast and lungs.