<p><strong>Noun</strong></p><ul><li>An Old World plant, <em>Marrubium vulgare</em>, of the mint family, having downy leaves and small, whitish flowers, and containing a bitter, medicinal juice that is used as an expectorant, vermifuge, and laxative.</li><li>Any of various plants of the mint family.</li><li>A brittle candy or lozenge flavored with horehound extract.</li></ul>