let loose something
US /lɛt luːs ˈsʌmˌθɪŋ/
UK /lɛt luːs ˈsʌmˌθɪŋ/

1.
풀어주다, 발산하다
to release something, often with force or without restraint
:
•
The dog was let loose in the park to run freely.
개는 공원에서 자유롭게 뛰도록 풀어졌다.
•
He let loose a string of curses after hitting his thumb.
그는 엄지손가락을 다친 후 욕설을 퍼부었다.