elephant cage
n.— «A structure similar to a fence of tall steel posts stands out in the distance. “We call that the elephant cage,” an officer says. It is the property of the 6921st Security Wing, a high-power electronic eavesdropping outfit that prefers to be identified, if at all, as having something to do with “communications.”» —“Jets From U.S. Base in Japan Patrol Near Soviet” by Robert Trumbull in Misawa, Japan New York Times June 12, 1966. (source: Double-Tongued Dictionary)