- slough (n.)
- "muddy place," O.E. sloh "soft, muddy ground," of uncertain origin, perhaps from P.Gmc. *slokhaz. Figurative use, e.g. of moral sunkenness or Bunyan's "Slough of Despond," attested from mid-13c.
- slough (v.)
- "to cast off" (as the skin of a snake or other animal), 1720, originally of diseased tissue, from M.E. noun slughe, slouh "shed skin of a snake" (c.1300), probably related to O.S. sluk "skin of a snake," M.H.G. sluch "snakeskin, wineskin," M.L.G. slu "husk, peel, skin," Ger. Schlauch "wineskin;" from P.Gmc. *sluk-, of uncertain origin, perhaps from PIE base *sleug- "to glide."