also chichi, "extremely chic, sophisticated," also, as a noun, "pretentious fussiness," 1908, from French chichi "airs, fuss." Perhaps, like frou-frou, imitative.
Entries linking to chi-chi
frou-frou n.
1870, "a rustling," from French (19c.), possibly imitative of the rustling of a dress. The word was popularized in English by a French play translated and given that name. Meaning "fussy details" is from 1876.