noun.
The melted rock ejected by a volcano from its top or fissured sides. It flows out in streams sometimes miles in length. It also issues from fissures in the earth's surface, and forms beds covering many square miles, as in the Northwestern United States.
noun.
a hard and coarse basaltic millstone from the neighborhood of the Rhine.
noun.
a kind of cheap pottery made of iron slag cast into tiles, urns, table tops, etc., resembling lava in appearance.