buy vs unload

buy

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

  • 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, especially by some sacrifice. 

  • to accept as true; to believe 

noun
  • Something which is bought; a purchase. 

unload

verb
  • To deposit one's load or cargo. 

  • To reduce the vertical load factor on (an airplane's wing or other lifting surface), typically by pitching downwards toward the ground to decrease angle of attack and reduce the amount of lift generated. 

  • To remove (the load or cargo) from a vehicle, etc. 

  • To give vent to or express; to unburden oneself of. 

  • To discharge, pour, or expel. 

  • To get rid of or dispose of. 

  • To remove the load or cargo from (a vehicle, etc.). 

  • To remove the charge from. 

  • To deliver forcefully. 

  • To ejaculate, particularly within an orifice. 

  • To remove (something previously loaded) from memory. 

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