Primus inter pares is a Latin phrase meaning first among equals. It is typically used as an honorary title for someone who is formally equal to other members of their group but is accorded unofficial respect, traditionally owing to their seniority in office.

Historically, the princeps senatus of the Roman Senate was such a figure and initially bore only the distinction that he was allowed to speak first during debate. Also, Constantine the Great was given the role of primus inter pares. However, the term is also often used ironically or self-deprecatingly by leaders with much higher status as a form of respect, camaraderie or propaganda. After the fall of the Republic, Roman emperors initially referred to themselves only as princeps despite having enormous power.

Various modern figures such as the chair of the Federal Reserve in the United States, the prime minister in parliamentary systems, the president of the Swiss Confederation, the chief justice of the United States, the chief justice of the Philippines, the archbishop of Canterbury of the Anglican Communion and the ecumenical patriarch of Constantinople of the Eastern Orthodox Church fall under both senses: bearing higher status and various additional powers while remaining still merely equal to their peers in important senses.