organ grinder
noun /ˈɔːɡən ɡraɪndə(r)/
  /ˈɔːrɡən ɡraɪndər/
- a person who plays a barrel organ (= a large musical instrument played by turning a handle)- (humorous) He's only the organ grinder's monkey (= an unimportant person who does what he is told to do).