What is En Passant?
1.
A French chess term, which describes a special pawn move made to take the pawn of the opponent "passing by".
After his opponent moved his pawn from c7 to c5, he took it moving his pawn on d5 to c6, so this move was "en passant".
See
2.
French chess term that means "Making up rules as you go."
Player 1: "Checkmate!"
Player 2: "You can't do that!"
Player 1: "En passant, bitch."
See