villain

1. A wicked or evil person; a scoundrel.
2. A dramatic or fictional character who is typically at odds with the hero.
3. (also vĭl'ān', vĭ-lān') Variant of villein.
4. Something said to be the cause of particular trouble or an evil: poverty, the villain in the increase of crime.
5. Obsolete. A peasant regarded as vile and brutish.

[Middle English vilein, feudal serf, person of coarse feelings, from Old French, from Vulgar Latin *vīllānus, feudal serf, from Latin vīlla, country house.]