lighten vs mollify

lighten

verb
  • To alleviate; to reduce the burden of. 

  • 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 become less serious or more cheerful. 

  • To make brighter or clearer; to illuminate. 

  • To make light or lighter in weight. 

mollify

verb
  • To ease a burden, particularly worry; make less painful; to comfort. 

  • To appease (anger), pacify, gain the good will of. 

  • To soften; to make tender 

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