emendation vs revisal

emendation

noun
  • The act of altering for the better, or correcting what is erroneous or faulty; correction; improvement. 

  • An intentional change in the spelling of a scientific name, which is usually not allowed. 

  • Alteration by editorial criticism, as of a text so as to give a better reading; removal of errors or corruptions from a document. 

revisal

noun
  • The act of revising; a revision. 

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