Echinus

Echinus may refer to:
 * Echinus (Acarnania), a town in ancient Acarnania, Greece
 * Echinus (Thessaly), a town in ancient Thessaly, Greece; also a Roman Catholic titular bishopric
 * Echinus (molding), a molding similar to the ovolo
 * Echinus (sea urchin), a genus of animals
 * Echinus (plant), a synonym for the plant genus Mallotus