ending vs expiry date

ending

noun
  • A termination or conclusion. 

  • The last part of something. 

  • The last morpheme of a word, added to some base to make an inflected form (such as -s in "dogs"). 

expiry date

noun
  • The date on which something runs out or expires and becomes out of date, in many cases needing renewal. 

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