swap out vs unload

swap out

verb
  • To exchange (something or someone) for an unused (or less-used) equivalent. 

  • To exchange (something) for (something else). (usually followed by with or for) 

  • To transfer (memory contents) into a swap file. 

noun
  • Anything that is swapped out for another; an exchange. 

  • A pre-prepared food item used in place of an unfinished food item in order to cut down the overall preparation time during filming. 

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 swap out and unload occurred in a corpus of books? (source: Google Ngram Viewer )