If "tdj" refers to the electronic artist TDJ , this could be an unofficial "hard" edit or a track from one of her "SPF" collections.
If this is a filename ending in .zip , it is likely a compressed folder containing audio stems, a "piece" of music production software, or a sample pack. Hard_tdjzip
Could you clarify where you encountered this name or if it’s a you are trying to open? If "tdj" refers to the electronic artist TDJ