constantly vs reiteratively

constantly

adv
  • In an unchangeable or invariable manner; in every case. 

  • In a constant manner; occurring continuously; persistently. 

  • Recurring regularly. 

reiteratively

adv
  • In a reiterative manner; by means of reiteration. 

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