1) Ball 2) Racquet sport 
Racquetball is a racquet sport played with a hollow rubber ball in an indoor or outdoor court. Joseph Sobek is credited with inventing the modern sport of racquetball in 1950 (the outdoor, one-wall game goes back to at least 1910 in N.Y.C.), adding a stringed racquet to paddleball in order to increase velocity and control. Unlike most racquet spor...
[n] - the ball used in playing the game of racquetball 2. [n] - a game played on a handball court with short-handled rackets
noun a game played on a handball court with short-handled rackets