approve vs buy

approve

verb
  • To consider worthy (to); to be pleased (with); to accept. 

  • To officially sanction; to ratify; to confirm; to set as satisfactory. 

  • To make profit of; to convert to one's own profit — said especially of waste or common land appropriated by the lord of the manor. 

  • To regard as good; to commend; to be pleased with; to think well of. 

buy

verb
  • to accept as true; to believe 

  • To make a purchase or purchases, to treat (for a drink, meal or gift) 

  • To make a bluff, usually a large one. 

  • To bribe. 

  • To be equivalent to in value. 

  • To obtain (something) in exchange for money or goods. 

  • To obtain, especially by some sacrifice. 

noun
  • Something which is bought; a purchase. 

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