41 C.F.R. §§ 102-83.70
A centralized community business area (CBA) or centralized business district, also commonly referred to as a central business district, is an area of concentration of commercial real estate and activity within a principal city, including other specific areas of similar character that may be recommended by local officials. The CBA may be part of a traditional downtown area or part of another area that local government officials have identified as supportive of their long-term economic development objectives. CBAs are designated by local governments and not by Federal agencies, so Federal agencies must consult and engage with local officials to understand the current boundaries of these areas. As described in E.O. 12072, these areas may include other specific areas that are recommended by local officials.
41 C.F.R. §§102-83.70