The Collaborative International Dictionary of English v.0.48:

Filth \Filth\ (f[i^]lth), n. [OE. filthe, ful[eth]e, AS.
   f[=y]l[eth], fr. f[=u]l foul; akin to OHG. f[=u]lida. See
   Foul, and cf. File.]
   1. Foul matter; anything that soils or defiles; dirt;
      nastiness.
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   2. Anything that sullies or defiles the moral character;
      corruption; pollution.
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            To purify the soul from the dross and filth of
            sensual delights.                     --Tillotson.
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   Filth disease (Med.), a disease supposed to be due to
      pollution of the soil or water.
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