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A Christogram (Latin Monogramma Christi ) is a monogram or combination of letters that forms an abbreviation for the name of Jesus Christ, traditionally used as a religious symbol within the Christian Church.

One of the oldest Christograms is the Chi-Rho. It consists of the superimposed Greek letters chi (Χ) and rho (Ρ), which are the first two letters of Greek χριστός "Christ". It was displayed on the labarum military standard used by Constantine I in AD 312. The IX monogram () is a similar form, using the initials of the name Ἰησοῦς (ὁ) Χριστός "Jesus (the) Christ", as is the ΙΗ monogram (), using the first two letters of the name Ἰησοῦς "Jesus".

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