The labarum () was a vexillum (military standard) that displayed the "Chi-Rho" symbol ?, formed from the first two Greek letters of the word "Christ" (, or Χριστ??) — Chi (χ) and Rho (ρ).In Unicode, the Chi-Rho symbol is encoded at U+2627 (?), and for Coptic at U+2CE9 (?).