A more thorough explanation:

A circuit judge is a public official who is appointed or elected to hear and decide legal matters in court. They are named as such in their commission and preside over a court. The term "judge" is often used interchangeably with "court."

For example, a federal judge who sits on a U.S. court of appeals is a circuit judge. They are responsible for hearing and deciding cases that are appealed from lower courts within their circuit. Another example is a family court judge who has jurisdiction exclusively over matters involving domestic relations, such as divorce and child custody matters.

Overall, a circuit judge is an important figure in the legal system who ensures that justice is served in a fair and impartial manner.