An inverted French phrase which means 'Do you speak'. Usually followed by 'Anglais' & used by anglophone Canadians & Americans who are too ignorant to even attempt to learn the French language before coming to a place that mostly French-speaking. If you say 'Non', they try to speak English to you anyway, as if the more slowly & loudly they speak it, the better you will comprehend it.
Stupid woman: "Parlez-Vous Anglais?"
Me, not wanting to deal with her: "Non, madame."
Stupid woman: "Are you sure?"
It means "Do you speak" in the French language.
Person 1: Parlez vous Francais?
Person 2: Oui. (oui means yes)