Villain
A villain is an Evil person, especially in Fiction. Villains are the fictional characters, or perhaps fictionalized characters, in Drama and Melodrama, who do Evil deliberately and work against the Hero. As such, villains are an almost inevitable Plot device, and more than the heroes, the villains are the crucial elements upon which plots turn. Female villains are sometimes called villainesses.
Word origin
The Etymology of the word could be from Old French Villein, in turn from Late Latin villanus, meaning serf or Peasant, someone who is bound to the soil of a villa, which is to say, worked on the equivalent of a Plantation in late Antiquity, in Italy or Gaul. Poverty was equated with moral turpitude; villains had to work their way up the social ladder. Thus usually the word villain suggests that the villain's schemes stem from their own Moral indifference or perversity of character.Another possible origin of this word is the Croatian legend of the three brothers Čeh, Meh, and Leh, who wanted to get rid of the Roman rule and establish unity in ancient Croatia, but their sister "Villana" was in love with a Roman prefect and betrayed her brothers plot. Villana was killed by her brothers.
Supervillains are found in the melodramatic environs of Superhero comic books, where an evil person with super powers is needed to be a challenging foil for the mighty heroes. These supervillains usually have recurring roles; some villains in more down to earth literature have become so popular that they have been reused in later works as well.
Stereotypes
There are many villain stereotypes. A caricature of a common cliché villain can be seen at the right of this page. In the era before sound in motion pictures villains had to appear very "visually" sinister, and thus many villain stereotypes were born. The Rocky and Bullwinkle characters Boris Badenov, Natasha Fatale, and Snidely Whiplash, as well as the Hanna-Barbera character Dick Dastardly, are well known parodies of this kind of character archetype.
These stereotypes include black clothing (often quite formal - capes, top hats, etc), facial hair, sharp features, and a perpetually "angry" facial expression. Other non-visual villainous stereotypes include a habit of "evil laughter," a snooty or smarmy voice, and a haughty overconfidence that leads to the unnecessary explanation of one's sinister plans. This exposition, of course, is a fairly transparent Plot device. There is an opposing stereotype of the beautiful villain who looks like a hero, but his/her personality and attitudes betray a diabolical nature. This especially came well known after World War II when the Holocaust was exposed which led to the popular villain who reflects the Nazi blond and blue eyed ideal, but that beauty hides an arrogant sense of his/her superiority and foul ambitions to make his/her "inferiors" suffer. The blond, blue-eyed villain has in recent time been extrapolated into a strange stereotype, the Evil Albino - a villain who displays several physical traits usually associated with Albinism (eg. pale skin, platinum blonde hair, blue or red eyes) despite not necessarily being supposed to suffer from that particular condition.
In Opera and Musical theater, the villain/villainess is played usually by a Baritone/Mezzo-soprano.