phrase
C2
When someone, especially a child, behaves without any control or rules.
During the summer, the kids are allowed to run wild in the backyard.
C2
When someone's thoughts or imagination are not controlled and become very active.
As I walked through the haunted house, my imagination began to run wild.
translation
When someone, especially a child, behaves without any control or rules.; When someone's thoughts or imagination are not controlled and become very active.