Dear supratim_c, Are we talking about some Navratna PSU, "The company is a reputed and branded one worldwide and has come into existence in the early sixties, and since then, the department is known as CPD"? If it is so, then my friend, the issue is not technical but rather a matter of jurisdiction and approval from the proper authority. In such matters, it is difficult to force the issue; however, do keep lobbying for it. You might be aware that many members tried to rename the NIPM (National Institute of Personnel Management), the premier all-India Institute of HR professionals, but so far, it has not yielded any result.
Many professionals have diverse opinions - some think that calling humans a 'resource' actually dehumanizes them. Some would prefer some other term like 'People Management'.
Once you get the proper approval from the competent authority, everything else - such as communicating the change - will follow.
Warm regards.