Lewis & Short

Hĕrŭli (Ĕrŭli), ōrum, m., the Herulians, the people of Northern Germany who penetrated into Italy and dissolved the western Roman Empire, Amm. 23, 1, 3; Paul. Diac. Longob. 1, 1; Claud. Mamert. Pan. ad Maxim. 5; Genethl. 7.
In sing. collect.: cursu Herulus, Sid. Carm. 7, 236.