executive
A person in charge who makes important decisions and runs things.
To be executive means having the power and responsibility to put decisions into action and make things happen. An executive is a person in a leadership position who runs an organization or makes important decisions about how it operates.
In business, executives like chief executive officers (CEOs) decide the direction of their companies: which products to make, who to hire, and how to spend money. In government, the executive branch carries out the laws that legislatures create. The President of the United States leads the executive branch, which means the President doesn't write the laws but is responsible for enforcing them and running the government day to day.
Executive work is about execution, turning plans and ideas into reality. When a school principal makes decisions about schedules, discipline, and hiring teachers, she's acting in an executive role. When the captain of a team decides the game strategy and assigns positions, he's taking executive action.
You might also hear executive used to describe something fancy or high-quality, like an executive office with a big desk and nice furniture. This usage reflects how executive positions typically come with more authority, responsibility, and sometimes luxury than other roles.