It is called “Christmas” because the word originally meant “Christ’s Mass,” referring to the Christian worship service celebrating the birth of Jesus Christ.

Name origin

The English word comes from Middle English forms like “Crīstesmæsse” and “Cristes-messe,” which literally mean “the mass of Christ.”

“Christ” itself comes from the Greek “Christos,” a translation of the Hebrew “Mashiach” (Messiah), both meaning “anointed.”

When the word appeared

Written uses of the word “Christmas” in English are recorded from at least the 11th–12th centuries.

Earlier, the celebration was often called the “Feast of the Nativity,” but over time “Christ’s mass” became the usual name in English.

Related terms and short forms

The “mass” part comes from Latin “missa,” the term for the Eucharistic service in Western Christianity.

The shortened form “Xmas” uses the Greek letter Chi (Χ), the first letter of “Christos,” so it is historically another way of writing “Christ’s Mass,” not removing Christ from the name.

TL;DR: It is called Christmas because it began as “Christ’s Mass,” the Christian church service celebrating Jesus Christ’s birth, and that phrase eventually became the standard English name for the holiday.

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