Villainy is wicked or evil behavior, especially when it's deliberate and meant to harm others. In stories, villainy is what the villain does: the evil queen's villainy in Snow White includes poisoning an innocent girl out of jealousy. The Sheriff of Nottingham's villainy in Robin Hood includes stealing from the poor and imprisoning anyone who stands up to him.

The word describes actions done with cruel intentions, often for selfish gain. Villainy involves planning and choosing to hurt others, not accidents or mistakes. When someone lies to get a classmate in trouble just to make themselves look better, that crosses from ordinary meanness into something closer to villainy.

In real life, villainy appears in histories of tyrants who abused their power, criminals who hurt innocent people, or corrupt leaders who betrayed their responsibilities. People use the word to emphasize that certain actions are genuine wickedness, not mistakes or poor judgment. The related word villain describes the person committing these acts, while villainy describes the evil deeds themselves.