<p><strong>Noun</strong></p><ul><li>Cerberuses, Cerberi</li><li>a dog, usually represented as having three heads, that guarded the entrance of the infernal regions</li><li>a formidable and often surly keeper or guard</li><li>a finned, 155 mm cannon-launched U.S. Army artillery shell that homes on the target, using the reflection of a laser beam projected by a forward observer</li></ul>