The expression used to indicate that the ball has not been struck in accordance with the rules "Not up" applies when 1) the ball is not struck correctly by the server or striker, 2) the ball bounces more than once upon the floor before being struck by the striker, 3) the ball touches the striker or anything that he wears or carries other than his racket, 4) the server makes an attempt but fails to strike the ball ("Not up" is also a Marker's call)