constate vs own up

constate

verb
  • To ascertain; to verify; to establish; to prove. 

  • To relay information in a statement and say whether it is true or false. 

own up

verb
  • to acknowledge, confess, or admit guilt or responsibility. Often used with to. 

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