The term 'Tennis Lesson Subject' can be summarized as a sport that requires the proper GRIP technique. GRIP is a four letter word that refers to the way a player holds the racket when playing tennis. It is important to have a good GRIP in order to hit the ball with accuracy and power. The GRIP also affects the spin of the ball, which can be used to create different types of shots. A tennis lesson subject would focus on teaching the student how to properly hold the racket and use it to their advantage.