chamber

Concise Oxford English Dictionary © 2008 Oxford University Press:
chamber/ˈtʃeɪmbə(r)/

▶noun

• 1 a large room used for formal or public events.

• 2 one of the houses of a parliament.

• 3 (chambers) Law, Brit. rooms used by a barrister or barristers, especially in the Inns of Court.

  ■ Law a judge's office, where proceedings may be held if not required to be held in open court.

• 4 archaic a private room, especially a bedroom.

• 5 an enclosed space or cavity.

  ■ the part of a gun bore that contains the charge.

• 6 [as modifier] Music of or for a small group of instruments: a chamber orchestra.

▶verb place (a bullet) into the chamber of a gun.

– derivatives
chambered adjective.

– origin ME: from OFr. chambre, from L. camera ‘vault, arched chamber’, from Gk kamara ‘object with an arched cover’.