Willfulness is stubborn determination to do what you want, especially when others tell you not to or when you know it’s wrong. A willful child might refuse to clean their room even after being asked five times, or insist on wearing shorts in a snowstorm despite everyone’s warnings.

The word captures deliberate, conscious defiance. Willfulness means you’re digging in your heels on purpose and choosing to resist. When a student willfully ignores the rules by talking during a test even after being warned, they’re making a conscious choice to disobey. When someone acts with willful disregard for safety, they know the risks and choose to ignore them anyway.

Sometimes willfulness appears harmless, like refusing to try new foods or insisting on doing things your own way. But willfulness becomes serious when it means rejecting good advice, breaking important rules, or refusing to cooperate when cooperation matters. A judge might talk about willful destruction of property, meaning someone damaged things on purpose, not by accident.

The related word willful describes someone or something showing this quality: a willful toddler or a willful decision to break a promise. Willfulness combines determination with defiance, strength with stubbornness.