brighten vs tar

brighten

verb
  • To make illustrious, or more distinguished; to add luster or splendor to 

  • To make more cheerful and pleasant; to enliven 

  • To grow bright, or more bright in color; to clear up 

  • To make bright or brighter in color. 

  • To become brighter or more cheerful in mood 

tar

noun
  • A file produced by such a program. 

  • A black, oily, sticky, viscous substance, consisting mainly of hydrocarbons derived from organic materials such as wood, peat, or coal. 

  • A Persian long-necked, waisted string instrument, shared by many cultures and countries in the Middle East and the Caucasus. 

  • A solid residual byproduct of tobacco smoke. 

  • A single-headed round frame drum originating in North Africa and the Middle East. 

  • Black tar, a form of heroin. 

  • Coal tar. 

  • A program for archiving files, common on Unix systems. 

verb
  • To besmirch. 

  • To create a tar archive. 

  • To coat with tar. 

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