The term BATTING-PRACTICE SETUP is used to describe the setup of a batting CAGE, which is a four-sided structure made of netting that is used to contain a baseball or softball during practice. The CAGE is typically set up in an open area, such as a field or gymnasium, and is designed to protect players and spectators from errant balls. The term CAGE is used to refer to the batting CAGE, which is the four-letter solution to this crossword puzzle.