The Collaborative International Dictionary of English v.0.48:

Moth \Moth\, n.; pl. Moths (m[o^]thz). [OE. mothe, AS.
   mo[eth][eth]e; akin to D. mot, G. motte, Icel. motti, and
   prob. to E. mad an earthworm. Cf. Mad, n., Mawk.]
   1. (Zool.) Any nocturnal lepidopterous insect, or any not
      included among the butterflies; as, the luna moth; Io
      moth; hawk moth.
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   2. (Zool.) Any lepidopterous insect that feeds upon garments,
      grain, etc.; as, the clothes moth; grain moth; bee moth.
      See these terms under Clothes, Grain, etc.
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   3. (Zool.) Any one of various other insects that destroy
      woolen and fur goods, etc., esp. the larvae of several
      species of beetles of the genera Dermestes and
      Anthrenus. Carpet moths are often the larvae of
      Anthrenus. See Carpet beetle, under Carpet,
      Dermestes, Anthrenus.
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   4. Anything which gradually and silently eats, consumes, or
      wastes any other thing.
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   Moth blight (Zool.), any plant louse of the genus
      Aleurodes, and related genera. They are injurious to
      various plants.

   Moth gnat (Zool.), a dipterous insect of the genus
      Bychoda, having fringed wings.

   Moth hunter (Zool.), the goatsucker.

   Moth miller (Zool.), a clothes moth. See Miller, 3,
      (a) .

   Moth mullein (Bot.), a common herb of the genus Verbascum
      (Verbascum Blattaria), having large wheel-shaped yellow
      or whitish flowers.
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