<p><strong>Noun</strong></p><ul><li>A plant belonging to the genus <em>Aconitum</em>, of the buttercup family, especially <em>A. napellus</em>, the flowers of which have a large, hood-shaped sepal.</li><li>False hellebore.</li><li>Any of several poisonous or medicinal substances extracted or prepared from these plants.</li></ul>