ambition vs need

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. 

need

verb
  • To want strongly; to feel that one must have something. 

  • To be obliged or required (to do something). 

  • To be required; to be necessary. 

  • To have an absolute requirement for. 

noun
  • Lack of means of subsistence; poverty; indigence; destitution. 

  • A requirement for something; something needed. 

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