Terminology
A DFP is known more commonly within United States Army slang as a "fighting position", or the slang term "ranger grave", within United States Marine Corps slang as a "fighting hole", in Australian and New Zealand Army Corps (ANZAC) forces terminology as a "fighting pit", in Australian Army terminology as a "Gun-Pit", within the British and Canadian military argot as a "slit trench", or simply—but less accurately—as a "trench".
Read more about this topic: Defensive Fighting Position