<p><strong>Verb</strong></p><ul><li>to collect or gather into a cluster or mass</li></ul><p><strong>Adjective</strong></p><ul><li>gathered together into a cluster or mass</li><li>crowded into a dense cluster, but not cohering</li></ul><p><strong>Noun</strong></p><ul><li>a mass of things clustered together</li><li>rock composed of rounded or angular volcanic fragments</li></ul>