continual vs unendly

continual

adj
  • Seemingly continuous; appearing to have no end or interruption. 

  • Recurring in steady, rapid succession. 

  • Forming a continuous series. 

unendly

adj
  • Having no end; infinite; endless; unending. 

adv
  • In an unendly or infinite manner; infinitely; unendingly. 

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