circumstantially vs unintentionally

circumstantially

adv
  • In respect to circumstances; not essentially; accidentally. 

  • in a circumstantial manner 

  • In every circumstance or particular; minutely. 

unintentionally

adv
  • In an unintentional manner; not intentionally. 

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