1. the head of state of a republic, especially the United States
2. the head of an organization, company, or institution

Examples

• The president will address the nation tonight.
• She was elected president of the United States.
• The company president announced new policies.
• He served as president of the university for ten years.
• The club members voted for a new president.
• The president signed the bill into law.
• She became the youngest president in the organization’s history.