Used to come back to anything someone says. Typically used when someone makes a statement to look hard or tough or like they actually know what the fuck they are talking about. You quickly act as the lawyer spreading doubt and say Or is it? Or does it? Or do they? et cetera!
Billy Bob "It's time to start working"
Smart person "Or is it?"
Billy Bob "This egg roll really hits the spot"
Smart person "Or does it?"
Billy Bob "stAve takes out the trash..."
Smart person "Or does he?"