let go vs slough

let go

verb
  • To dismiss from employment. 

  • To release from one's grasp; to go from a state of holding on to a state of no longer holding on. 

  • To ignore (a comment, etc.). 

  • To emotionally disengage or to distract oneself from a situation. 

  • To fail to maintain a standard of appearance, behavior, or performance. 

  • Used other than figuratively or idiomatically: see let, go. 

  • To gain weight 

slough

verb
  • To discard. 

  • To shed (skin). 

  • To slide off (like a layer of skin). 

  • To commit truancy, be absent from school without permission. 

noun
  • A small pond, often alkaline, many but not all formed by glacial potholes. 

  • Dead skin on a sore or ulcer. 

  • A muddy or marshy area. 

  • A type of swamp or shallow lake system, typically formed as or by the backwater of a larger waterway, similar to a bayou with trees. 

  • A state of depression. 

  • The skin shed by a snake or other reptile. 

  • A secondary channel of a river delta, usually flushed by the tide. 

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