Aprovement or Approvement: How To spell?

The word Aprovement is misspelled against Approvement, a noun meaning "a confession of guilt by a prisoner charged with treason or felony, together with an accusation of his accomplish and a giving evidence against them in order to obtain his own pardon. The term is no longer in use; it corresponded to what is now known as turning king's (or queen's) evidence in England, and state's evidence in the United States."