A triumvirate is a group of three people who share power and authority. It comes from the Latin phrase "tres viri", which means "three men". In history, a triumvirate was used to share the power of rulers in a government. For example, Julius Caesar, Pompey and Crassus formed a triumvirate to rule the Roman Empire. The three people shared the power and authority to make decisions, give orders and make laws. These days, it is often used to describe a group of three very powerful or influential people in a company, organization or country.