galling vs rankling

galling

adj
  • Vexing, humiliating; eliciting indignation or bitterness. 

noun
  • Material transfer caused by adhesion between sliding surfaces, potentially resulting in wear or binding. 

rankling

noun
  • A sensation that rankles. 

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