What is the difference, if any, between marsh, slough and swamp? What is the difference, if any, between marsh, slough and swamp? All three words get translated to the Dutch word 'moeras'. A 'moeras' for me is an area with a lot of water, pounds, quick sand. You have to be careful where you walk, you could drown and there are a lot of insects, especially mosquitos and in the tropics you can get malaria.