yùn​dòng​chǎng

exercise yard

运动场 (運動場) yùn​dòng​chǎng
exercise yard noun
an enclosed outdoor space for physical activity, especially in a prison or institutional setting

The prison's sports field is surrounded by high walls.

sports field noun
an outdoor area designed for athletic competition or physical training

This university has a modern sports field.

Frequency

Movie subtitles
2.50 per million appears in 1% of films
Written text
1.55 per million

Sources

Definitions
CC-CEDICT