The French are very prone to picking up English words and Frenchifying them, much to the chagrin of the French language police and yes, they do have such a thing.
Yeah, I wondered if this was such a case. There is tremendous irony in having a movement in France which is seeking to promote French sovereignty and national identity but ends up using an frenchified English word to describe it. The language police must be shaking their heads.
So I wonder what they would call Brussels exiting? Name’s been taken already.