pejoration vs rot

pejoration

noun
  • The act or process of becoming worse; worsening or degeneration. 

  • The process by which a word acquires a more negative meaning over time. 

rot

noun
  • The process of becoming rotten; putrefaction. 

  • Any of several diseases in which breakdown of tissue occurs. 

  • Verbal nonsense. 

  • Decaying matter. 

verb
  • To expose, as flax, to a process of maceration, etc., for the purpose of separating the fiber; to ret. 

  • To spend a long period of time (in an unpleasant place). 

  • To suffer decomposition due to biological action, especially by fungi or bacteria. 

  • To decline in function or utility. 

  • To (cause to) deteriorate in any way, as in morals; to corrupt. 

  • To make putrid; to cause to be wholly or partially decomposed by natural processes. 

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