noun
1. : an act or behavior that gravely violates the moral sentiment or accepted moral standards of the community ; especially : sexual immorality
was considered unfit to hold office because of moral turpitude
2. : the morally culpable quality held to be present in some criminal offenses as distinguished from others
permits may be denied for bad moral character … or conviction for an offense involving moral turpitude — David Fellman
— compare malum prohibitum