What are the members of the Supreme Court called?

Generally, they are called Justices. The Supreme Court has one Chief Justice and eight Associate Justices.

Titles

As a group, members of the US Supreme Court are called justices, not judges.

The head of the Court is known as the Chief Justice; his or her official title would be Chief Justice of the United States.

The other eight Justices are called Associate Justices.

Status

The most recent member of the Court may also be referred to as the Junior Justice.

The Justice with the most seniority may also be referred to as the Senior Justice.

Neither Junior Justice nor Senior Justice are official titles, however.

Addressing the Court

When referring to a specific person, they are addressed as Justice [last name] or Mr./Ms. Justice [last name]. The Chief Justice is called Chief Justice [last name].