【Villain】 , 【scoundrel】 , 【blackguard】 , 【knave】 , 【rascal】 , 【rogue】 , 【scamp】 , 【rapscallion】 , 【miscreant】 can all denote a low, mean, and reprehensible person utterly lacking in principles.
【Villain】 describes one utterly given to crime, evil, and baseness.
【Scoundrel】 may suggest blended worthlessness, meanness, and unscrupulousness.
【Blackguard】 may imply inveterate depravity; sometimes it is used with a suggestion of angry contempt as the antithesis of gentleman .
【Knave】 may suggest sly trickery and deceit.
【Rascal】 may suggest base dishonesty.
【Rogue】 often suggests the blended roughness and wiliness of a vagabond, but both 【rascal】 and 【rogue】 are freely used with greatly weakened force and then imply no more than a more or less pleasing mischievousness.
【Scamp】 may describe one given to artful cheating, clever robbery, or interesting escapades and it, too, is often used with weakened force, then suggesting impish and often childish trickery.
【Rapscallion】 may refer to an ill-dressed 【rogue】 or 【rascal】 rarely successful.
【Miscreant】 typically refers to a singularly conscienceless 【villain】 .