A villain is the bad guy in a story, the character who creates problems for the hero and often tries to do evil or harmful things. In The Lion King, Scar is the villain who plots against Simba. In Star Wars, Darth Vader begins as a terrifying villain who threatens the galaxy. The Wicked Witch of the West terrorizes Dorothy throughout The Wizard of Oz.

What makes someone a villain is having harmful goals and actively working against the good characters. They might want power, revenge, or treasure, and they're willing to hurt others to get it. The villain is the obstacle the hero must overcome, the source of danger and conflict that makes the story exciting.

Outside of stories, people sometimes call someone a villain when that person has done something really wrong or hurtful. A newspaper might describe a criminal as the villain in a real-life crime. When your friend jokingly blames you for eating the last cookie, they might call you the villain playfully, not seriously.

The word villainous describes behavior worthy of a villain: cruel, sneaky, or evil. A villainous plot is a scheme designed to harm others or do something wicked.