(American.) 1. An enlargement in a cave passage or system, commonly formed at a junction of passages, or locally in a single passage, where erosion has been enhanced by collapse exposing more rock to dissolution. Maximum chamber size is controlled by the strength and shape of the limestone ceiling. The largest chamber currently known, Sarawak Chamber in Lubang Nasib Bagus, at Mulu, Sarawak, is over 700m long, up to 400m wide and nowhere less than 70m high. It has formed where a large stream eroded sideways as it cut obliquely across the included bedding in unusually massive limestone. It is doubtful whether a much larger chamber could exist without collapse of its roof . 2. The largest order of cavity in a cave or cave system; it has considerable length and breadth but not necessarily great height. 3. (British.) A room in a cave . Synonyms: (French.) salle; (German.) Halle, Kammer, Dom; (Greek.) ypoyios aethousa; (Italian.) sala; (Russian.) zal; (Spanish.) sala, salon; (Turkish.) oda; (Yugoslavian.) dvorana. See also room; passage.