a. An area having a wet, spongy, acidic substrate composed chiefly of sphagnum moss and peat in which characteristic shrubs and herbs and sometimes trees usually grow.
b. Any of certain other wetland areas, such as a fen, having a peat substrate. Also called peat bog.
To cause to sink in or as if in a bog: We worried that the heavy rain across the prairie would soon bog our car. Don't bog me down in this mass of detail.