(n.) 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.
APPROVEMENT
Meaning of APPROVEMENT in English
Webster's English dictionary. Английский словарь Webster. 2012