Interesting... I had thought/understood that it stood for "dead cold", meaning the amp handled frequencies beginning from "zero Hz" (well, technically I guess it would start at one Hz, since true dead cold would be absolute silence/lack of vibration). Don't remember where I read that, but I know I read it somewhere.
It's a nice amp...worth getting if the price is right and you are looking for a solid-state amp in that power range.