playmate
n. countable B1 Intermediate US //ˈpɫeɪˌmeɪt// UK //plˈeɪmeɪt// play·mate
n. a child that you play with. It is a funny or slightly old-fashioned word for a friend you have fun with.
n. a child with whom one plays. Often carries a humorous or slightly archaic tone in modern usage.
The two boys became playmates at the park.
After school, she would often meet her best playmate at the local playground to share snacks.
The children's playmate was a local boy who had recently moved into the neighborhood, bringing with him a collection of rare wooden toys.
From play + mate. Compare earlier playfeer (“playmate”) of similar construction.