split one's sides (with laughter)
to laugh so hard that one's sides almost split
I split my sides with laughter when the woman began to tell jokes.
Rules to play Squash
A Good Return
A return is good if the ball, before it has bounced twice on the floor, is returned by the striker on to the front wall above the tin, without touching the floor or any part of the strikers body or clothing, provided the ball is not hit twice, down or out.