The word "caitiff" meaning
Webster's sense 2 (
Base; wicked and mean; cowardly; despicable) comes from the medieval
Latin phrase "Captivus diaboli", that is "Prisoner of the devil". This phrase was used to address
heretics,
assassins,
excommunicates,
prostitutes and other people ruled out of the
civil society.
This meaning has passed to some neo-Latin languages like Italian where the word cattivo does not have the correct Latin meaning of prisoner but rather of an evil person as first meaning.