1. the state or fact of having a duty to deal with something or of having control over someone
2. the state or fact of being accountable or to blame for something
3. a thing that one is required to do as part of a job, role, or legal obligation

Examples

• Parents have the responsibility to care for their children.
• She accepted full responsibility for the mistake.
• It's your responsibility to lock the door when you leave.
• The company denied responsibility for the accident.
• Managing the budget is one of his main responsibilities.
• With great power comes great responsibility.
• Taking responsibility for your actions shows maturity.