Self-possessed means staying calm, confident, and in control of yourself, especially when things get stressful or chaotic around you. A self-possessed person doesn't panic during emergencies, doesn't get flustered when speaking in front of others, and keeps their composure even when unexpected problems arise.

Think of a student who walks into class and discovers there's a surprise quiz. While some classmates might groan or scramble nervously, a self-possessed student takes a deep breath, picks up their pencil, and calmly does their best. Or imagine a soccer goalie who stays focused and steady even when the other team scores. That's being self-possessed.

The word suggests an inner strength that comes from knowing yourself and trusting your abilities. Self-possessed people don't need to act tough or show off. They simply remain steady and clearheaded, which helps them think better and perform better under pressure.

You might also hear the related word poise, which means grace and composure. A self-possessed person has poise. When someone loses their self-possession, they might become rattled, anxious, or scattered. Developing self-possession takes practice, but it's a quality that helps in everything from schoolwork to sports to handling life's surprises.