English "Xmas" (or slightly variant forms) is a written abbreviation for "Christmas"
1We first noticed the spread of this cuteness just before X-mas.
2By X-mas 1952 the lenient-treatment was flourishing so that the men were permitted a mild celebration.
3L. gave no tips but gave $500 at X-mas.
4We're counting down the final days of the X-Mas season and it's way past the cut-off for determining who has been naughty or nice.