deoxidation vs subtraction

deoxidation

noun
  • The process of extracting the oxygen content of a dissolved oxide, or of removing dissolved oxygen, with the aid of a reducing agent. 

subtraction

noun
  • The removal of something. 

  • The process of subtracting a number from another. 

  • A calculation involving subtracting. 

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