A tract of land covered with peat, which holds much water and converts it into a kind of quagmire. It is sometimes called Peat-bog, Peatmoss, or Moss, to distinguish it from other kinds of swamp. Bogs of wide extent occur in Northern lands and they cover a considerable part of Ireland. Some bogs are more than 40 feet in depth, and are dangerous to traverse in wet seasons. (See Peat.)