VOLCA'NO, noun 1. In geology, an opening in the surface of the earth or in a mountain, from which smoke, flames, stones, lava or other substances are ejected. Such are seen in Etna and Vesuvius in Sicily and Italy, and Hecla in Iceland. It is vulgarly called a burning mountain. Herschel has discovered a volcano in the moon. 2. The mountain that ejects fire, smoke, etc.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI