Defiance is the bold refusal to obey someone or follow a rule, even when you know there will be consequences. When someone acts in defiance, they're standing up and saying “no” to authority or expectations, often because they believe something is wrong or unfair.

You see defiance when a student refuses to apologize for something they didn't do, even though the teacher insists. You see it when colonists threw tea into Boston Harbor rather than pay taxes they considered unjust. Defiance means deliberately choosing not to comply, usually to make a point or protect a principle.

The word carries a sense of courage mixed with stubbornness. Sometimes defiance leads to positive change, like when Rosa Parks showed defiance by refusing to give up her bus seat during the Civil Rights Movement. Other times, defiance just creates unnecessary conflict, like refusing to wear a helmet while biking simply because someone told you to.

Defiant is the adjective form. A defiant look on someone's face shows they won't back down. When you act in defiance of a rule, you're breaking it openly rather than sneaking around. The key element is that defiance is visible and intentional: you want others to know you're refusing to comply.