contra vs swap out

contra

noun
  • A deal to swap goods or services. 

  • A conservative; originally tied to Nicaraguan counter-revolutionaries. 

  • An entry (or account) that cancels another entry (or account). 

  • Any of the musical instruments in the contrabass range, e.g. contrabassoon, contrabass clarinet or, especially, double bass. 

  • A contra dance. 

adv
  • contrary to something 

prep
  • against; contrary or opposed to; in opposition or contrast to 

verb
  • To undo; to reverse. 

swap out

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. 

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

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

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

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