means A low-lying, waterlogged stretch of land where soggy ground and standing water nurture trees, reeds, and a thriving tangle of muck-loving life.

from From the Germanic family of words for spongy, soft ground — English 'swamp' is likely related to old Germanic terms meaning 'sponge' or 'fungus,' the same soggy root that gives us 'sump.' It surfaced in English around the early 1600s, often in the mouths of colonists describing the boggy wilds of the New World, and quickly took on the sense of any impassable, water-choked low ground.