What is the X in X-mas?
1870, "a rustling," from French (19c.), possibly imitative of the rustling of a dress. Meaning "fussy details" is from 1876.
Frilly dress and adornment; frivolous bedizenment: Is that what you want in a girl, chi-chi, frou-frou, fancy clothes, permanent waves?
[1870+; fr French, imitative of the rustling of silk]