CEO

n. head manager of a company or large organization, managing director

A Chief Executive Officer (CEO), or chief executive, is the highest-ranking corporate officer, administrator, corporate administrator, executive, or executive officer, in charge of total management of a corporation, company, organization or agency.
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Noun
1. the corporate executive responsible for the operations of the firm; reports to a board of directors; may appoint other managers (including a president)
(synonym) chief executive officer, chief operating officer
(hypernym) corporate executive, business executive

CEO, Chief Executive Officer, head manager of a company or large organization

A title held often by the Chairman of the Board, president, vice-chairman, which is given to the person principally responsible for the activities of a company.