of Labarum
Source: Webster's dictionaryA Companion to Roman Religion edited by Jörg Rüpke 2011 ISBN 1-4443-3924-9 page 159 Eusebius stated that in addition to the singular labarum of Constantine, other similar standards (labara) were issued to the Roman army. Source: Internet
This is confirmed by the two labara depicted being held by a soldier on a coin of Vetranio (illustrated) dating from 350. Later usage Modern ecclesiastical labara (Southern Germany). Source: Internet