What is the X in X-mas?
1670s, from Modern Latin striatus, from Latin stria (see striation). Related: Striated; striating.
striate stri·ate (strī'āt')v. stri·at·ed, stri·at·ing, stri·ates To mark with striae or striations. adj. or stri·at·ed (-ā'tĭd)
Marked with striae; striped, grooved, or ridged.
Consisting of a stria or striae.