What is Bench?

Legal Definition
Bench in legal contexts means simply the location in a courtroom where a judge sits. The historical roots of that meaning come from judges formerly having sat on long seats or benches (freestanding or against a wall) when presiding over a court. In modern courtrooms, the bench is usually an elevated desk area that allows a judge to view the entire courtroom.

The word also has a broader meaning in the law – the term "bench" is a metonym used to describe members of the judiciary collectively, or the judges of a particular court, such as the Queen's Bench or the Common Bench in England and Wales, or the federal bench in the United States. The term is also used when all the judges of a certain court sit together to decide a case, as in the phrase "before the full bench" (also called "en banc"). Additionally, the term is used to differentiate judges ("the bench") from attorneys or barristers ("the bar"). The phrase "bench and bar" denotes all judges and lawyers collectively.
-- Wikipedia
Legal Definition
The term the bench refers to judges and comes from the name of the place in the courtroom where the judge sits.
Legal Definition
Latin Bancus, used for tribunal. In England there are two courts to which this word is applied. Bancus Regius, King's Bench Bancus Communis, Com- mon Bench or Pleas. The jus banci, says Spelman, properly belongs to the king's judges, who administer justice in the last resort. The judges of the inferior courts, as of the barons, are deemed to, judge plano pede, and are such as are called in the civil law pedanei judices, or by the Greeks Xauaidixastai, that is, humi judicantes. The Greeks called the seats of their higher judges Bumata, and of their inferior judges Bathra. The Romans used the word sellae and tribunalia, to designate the seats of their higher judges, and subsellia, to designate those of the lower. See Spelman's Gloss. (ad verb.) Bancus; also, 1 Reeves Hist. Eng. Law, 40, 4to ed., and postea Curia Regis.
-- Bouviers Law Dictionary
Legal Definition
A seat of judgment or tribunal for the administration of justice; the scat occupied by judges in courts; also the court itself, as the "King's Bench," or the aggregate of the judges composing a court, as in the phrase "before the fnil bench." The collective body of the judges in a state or nation, as distinguished from the body of attorneys and advocates, who are called the "bar." In English ecclesiastical law. The aggregate body of bishops.
See also
-- Black's Law Dictionary
Legal Definition
A court; the judges of a court.
-- Ballentine's Law Dictionary