Meaning

noun a wicked or evil person; someone who does evil deliberately

noun the principal bad character in a film or work of fiction

originProbably from Middle English vilein, from Old French vilein (modern French vilain), in turn from Late Latin vīllānus, meaning serf or peasant, someone who is bound to the soil of a Latin vīlla, which is to say, worked on the equivalent of a plantation in late Antiquity, in Italy or Gaul. Doublet of villein. Compare typologically pagan (see more).

Etymology from Wiktionary, CC BY-SA 3.0