racquetball       
noun uk/ˈræk.ɪtˌbɔːl/ us/ˈræk.ɪtˌbɑːl/
 [ U ]壁球 
a game played in an enclosed playing area between two or four people who use rackets to hit a small rubber ball against a wall
  They meet to play racquetball once a week.
 He challenged me to a game of racquetball.
 - More examples
 - He pulled a muscle in his back playing racquetball.
 - His workout plan consisted of weightlifting, sprints, distance running, and racquetball.
 - The building contains a racquetball court.
 - She's an excellent racquetball player.
 - You could build up strength by squeezing a racquetball.