lighten vs worry

lighten

verb
  • To become less serious or more cheerful. 

  • To become light or lighter in weight. 

  • To become brighter or clearer; to brighten. 

  • To make less serious or more cheerful. 

  • To illuminate with knowledge; to enlighten. 

  • To descend; to light. 

  • To emit or disclose in, or as if in, lightning; to flash out, like lightning. 

  • To alleviate; to reduce the burden of. 

  • To make brighter or clearer; to illuminate. 

  • To make light or lighter in weight. 

worry

verb
  • To be troubled; to give way to mental anxiety or doubt. 

  • To harass; to irritate or distress. 

  • To touch repeatedly, to fiddle with. 

  • To seize or shake by the throat, especially of a dog or wolf. 

  • Disturb the peace of mind of; afflict with mental agitation or distress. 

noun
  • A strong feeling of anxiety. 

  • An instance or cause of such a feeling. 

  • A person who causes worry. 

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