This one has bugged me for a while…
If you hear someone in France talking about the “vay-say”, which you would probably write as “VC”, it’s not the Viet Cong or the Victoria Cross or Venture Capital, or something like this.
It’s actually not even VC. It’s supposed to be “WC”, but apparently the “double” is too difficult to say. So instead of “dooble-vay say”, it becomes “vay say”. So it means WC. Which is actually English for Water Closet.
So, in France, via tortured evolution, one way to say toilet in French is “vay-say”.