ambition vs brighten

ambition

verb
  • To seek after ambitiously or eagerly; to covet. 

noun
  • Eager or inordinate desire for some object that confers distinction, as preferment, honor, superiority, political power, or fame; desire to distinguish one's self from other people. 

  • An object of an ardent desire. 

  • A personal quality similar to motivation, not necessarily tied to a single goal. 

  • A desire, as in (sense 1), for another person to achieve these things. 

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 

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