labarum
/ˈlæbərəm/
noun
- A military standard or banner, especially the one used by the Roman emperor Constantine that featured Christian symbols.
- Historians study the labarum as a symbol of Constantine's conversion to Christianity.
- The museum displayed a replica of the ancient labarum with its famous chi-rho symbol.
- The labarum was carried at the front of the Roman army to inspire the soldiers.