From Longman Business DictionaryChinese wallChi‧nese wall /ˌtʃaɪniːz ˈwɔːl-ˈwɒːl/ noun [countable usually plural] FINANCE in certain financial institutions, an action to stop secret information passing between departments where one department could gain from the information. For example, a department buying and selling shares might gain from information from the department that gives advice on MERGERs (=when one company joins with another to form one larger company)The securities commission fined the financial group for failing to maintain Chinese walls between its corporate finance and broking arms.
