adjective

1. having a very bad reputation; notorious; in disgrace or dishonor
2. causing or deserving a bad reputation; scandalous; outrageous
3. Law
   1. punishable by imprisonment in a penitentiary: said of certain crimes, usually felonies
   2. guilty of such a crime

Etymology: ME < OFr infameux < ML infamosus < L infamis: see in- & famous