Infamy is a term of art in Roman Catholic Canon Law. The remainder of this article discusses infamy as defined by Canon Law. According to the Catholic Encyclopedia of 1913, infamy in the canonical sense is defined as the privation or lessening of one's good name as the result of the bad rating which he has, even among prudent men. It constitutes an irregularity, i.e. a canonical impediment which prevents one being ordained or exercising such orders as he may have already received.
There are two types of infamy, infamy of law (infamia juris) and infamy of fact (infamia fact).
A crime consisting in acts which society not only forbids but also considers as highly immoral and particularly dishonoring, as defined (variously) in certain legal systems, as in Poland; in its origin, in Ancient Rome, infamia was the mark of disapproval of the censors on moral grounds - often such 'legal immorality' is largely defined according to the state - or de facto dominant religion.
In the Polish-Lithuanian Commonwealth infamy (infamia) was a more severe form of exile sentence. A noble who has been sentenced to infamy, known as infamis lost the protection of the law and there was a reward for his death. In addition, an exiled noble (banita) who killed an infamed one could expect his exile sentence to be revoked.