swap out vs vicissitude

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. 

vicissitude

noun
  • A change, especially in one's life or fortunes. 

  • Regular change or succession from one thing to another, or one part of a cycle to the next; alternation; mutual succession; interchange. 

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