If you have a question that you think might interest other readers, please ask . The TGV brand is now a trademark, although the acronym remains a general term. It can refer to the trains, it can refer to the high speed lines, it can refer to the entire French high speed rail system.
Usage varies and depends on context.
It's important to keep in mind that TGV means more than just the trains. By themselves they can't go much faster than conventional trains, and to achieve their potential special tracks and signalling are required. Therefore, the TGV is also a system . Yes, very safe. The high speeds have resulted in no fatalities two decades of operations.