plugging vs tiring

plugging

noun
  • The material of which a plug or stopper is made. 

  • An arrangement of plugs. 

  • The act of stopping with a plug. 

tiring

noun
  • Bits of bone and tough organic material from a corpse given to hawks to abate their hunger. 

  • The action of tiring. 

adj
  • That tires or tire. 

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