Definitions of slough:

• noun:   any outer covering that can be shed or cast off (such as the cast-off skin of a snake)
• noun:   a stagnant swamp (especially as part of a bayou)
• noun:   a hollow filled with mud
• noun:   necrotic tissue; a mortified or gangrenous part or mass
• verb:   cast off hair, skin, horn, or feathers
• name:  A surname (very rare: popularity rank in the U.S.: #18928)