alteration vs recension

alteration

noun
  • The act of altering or making different. 

  • The state of being altered; a change made in the form or nature of a thing; a changed condition. 

recension

noun
  • A critical revision of a text. 

  • A family of manuscripts which share similar traits; the variety of a language which is used in such manuscripts. 

  • A census, an enumeration, a review, a survey. 

  • A text established by critical revision. 

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