Noun
black chamber (plural black chambers)
(historical, cryptography, informal) A government or royal court's cryptanalyst department.
Codebooks and codebook publishers proliferated, including one run as a front for the American Black Chamber run by Herbert Yardley between the First and Second World Wars. Source: Internet
Prototype of Red Japanese diplomatic communications at negotiations for the Washington Naval Treaty were broken by the American Black Chamber in 1922, and when this became publicly known, there was considerable pressure to improve their security. Source: Internet
The American Black Chamber. Source: Internet
Manatt also continues to be the registered lobbying firm for the California Black Chamber of Commerce. Source: Internet
The Greater Austin Black Chamber of Commerce remains dedicated to providing resources, technical assistance and leadership while promoting the development and expansion of African American and greater Austin area businesses communities. Source: Internet