Xmas - origin

Why do religious Jews say "Xmas" instead of "Christmas" and why X and not Y or Z?

Here in NY and I think in most of the US, Xmas is just an abbreviation for "Christmas".

"X" is a symbol for Christ, from the Greek letter chi (X). Christ + mas = X + mas = Xmas

Maybe in other regions of the globe "xmas" has taken on some other nuance besides being just an abbreviation.

It's just an abbreviation in Britain.

Not only Jews write "Xmas"; it appears often in advertising. The Xmas question came up last month; use link below for a more thorough answer (URL is www.phrases.org.uk bulletin_board 11 messages 939.html).