“Xmas” is actually a Christian abbreviation, one whose origins date back at least a thousand years. The term derives from the Greek letter chi, which resembles the English letter X and is the first letter in the word Christ as it is spelled in the Greek alphabet. References to “XPMas” as an abbreviation for “Christmas” can be found as early as the Anglo-Saxon Chronicle in 1021 CE. (The P is the Greek letter rho; the chi-rho combination is an ancient Christian symbol known as the Labarum.)
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