Trivia!

Last time I asked:- This color became popular in the late eighteenth century, despite being named for a pest.

Lauren R managed to beat everyone else to the punch and correctly stated that it was "Puce" which we all know means "flea". There were actually several variations on the color, but traditionally it is held to be a sort of brownish-purple.

This week my query is:-

What french word came to describe all of the ex-aristocrats who fled France after the Revolution of 1789?