bog,
peat bog wet spongy ground of decomposing vegetation; has poorer drainage than a swamp; soil is unfit for cultivation but can be cut and dried and used for fuel
slough -
a stagnant swamp (especially as part of a bayou)
slough -
necrotic tissue; a mortified or gangrenous part or mass
Slough is a borough and unitary authority within the ceremonial county of Berkshire, England. The town stands athwart the Great West Road and the Great Western Main Line, 19 miles (31 km) west of central London. At the 2001 census, the population of Slough was 119,070 (est.