noun (n)

• the precipitate produced by sewage treatment(noun.substance)

  source: wordnet30
• any thick, viscous matter(noun.substance)

  Synonym:
  goo, gook, goop, guck, gunk, muck, ooze, slime
  

  source: wordnet30
• Mud; mire; soft mud; slush.(noun)

  source: webster1913
• Anything resembling mud or slush; as: (a) A muddy or slimy deposit from sweage. (b) Mud from a drill hole in boring. (c) Muddy sediment in a steam boiler. (d) Settling of cottonseed oil, used in making soap, etc. (e) A residuum of crude paraffin-oil distillation.(noun)

  source: webster1913