noun A large open space for children to play in, usually having dedicated play equipment (such as swings and slides). .mw-parser-output .defdate{font-size:smaller}
The kids have to go to the playground during recess, no matter the weather.
noun Any physical or metaphysical space in which a person or organization has free rein to do as they please.
The exclusive tropical island was a millionaire's playground.
noun A sandbox for testing calls to an application programming interface.