chief justice

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The presiding judge of a high court having several judges, especially the US Supreme Court.

from the GNU version of the Collaborative International Dictionary of English.

• The presiding justice, or principal judge, of a court.
• The presiding judge of the Queen's Bench Division of the High Court of Justice. The highest judicial officer of the realm is the Lord High Chancellor.
• the presiding judge of the Supreme Court, and Highest judicial officer of the republic.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the judge who presides over a supreme court