locks vs sidelock

locks

noun
  • A head of hair; tresses. 

  • Dreadlocks. 

sidelock

noun
  • A lock of hair worn at the side of the head. 

  • The design of a gun that has the lockwork mounted to the inside of a plate; compare boxlock. 

How often have the words locks and sidelock occurred in a corpus of books? (source: Google Ngram Viewer )