annex vs append

annex

verb
  • To add something to another thing, especially territory; to incorporate. 

  • To attach or connect, as a consequence, condition, etc. 

  • To join; to be united. 

noun
  • An appendix to a book or document. 

  • An addition to the territory of a country or state, from a neighbouring country or state, normally by military force. 

  • An addition, an extension. 

  • An addition or extension to a building. 

append

verb
  • To add, as an accessory to the principal thing; to annex 

  • To write more data to the end of a pre-existing file, string, or other object. 

  • To hang or attach to, as by a string, so that the thing is suspended 

noun
  • An instance of writing more data to the end of an existing file. 

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