perpetual vs unended

perpetual

adj
  • Continuing; uninterrupted. 

  • Set up to be in effect or have tenure for an unlimited duration. 

  • Lasting forever, or for an indefinitely long time. 

  • Flowering throughout the growing season. 

unended

adj
  • Not ended. 

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