let somebody/something loose
(with something) Go to let go (with something).
let ˈloose(British English) (American English cut ˈloose) (informal) do something or happen in a way that is not controlled: Teenagers need a place to let loose.
let somebody/something ˈloose
1 free somebody/something from whatever holds them/it in place: She let her hair loose and it fell around her shoulders. ♢ Who let the dogs loose?
2 give somebody complete freedom to do what they want in a place or situation: He was at last let loose in the kitchen. ♢ A team of professionals were let loose on the project.