kids' room; children's playroom
A room or area designed for children to play, often found in department stores, airports, or family restaurants.
デパートのキッズルームで子どもを遊ばせた。
I let my child play in the department store's kids' room.
空港にキッズルームがあると助かる。
It's helpful when there's a kids' room at the airport.