The Collaborative International Dictionary of English v.0.48:

Molt \Molt\, Moult \Moult\, v. t.
   To cast, as the hair, skin, feathers, or the like; to shed.
   [1913 Webster] Molt

The Collaborative International Dictionary of English v.0.48:

Molt \Molt\, Moult \Moult\, n.
   The act or process of changing the feathers, hair, skin,
   etc.; molting.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Molt \Molt\, obs.
   imp. of Melt. --Chaucer. --Spenser.
   [1913 Webster] Molt

The Collaborative International Dictionary of English v.0.48:

Molt \Molt\, Moult \Moult\, v. i. [imp. & p. p. Molted or
   Moulted; p. pr. & vb. n. Molting or Moulting.] [OE.
   mouten, L. mutare. See Mew to molt, and cf. Mute, v. t.]
   [The prevalent spelling is, perhaps, moult; but as the u
   has not been inserted in the otherwords of this class, as,
   bolt, colt, dolt, etc., it is desirable to complete the
   analogy by the spelling molt.]
   To shed or cast the hair, feathers, skin, horns, or the like,
   as an animal or a bird. --Bacon.
   [1913 Webster] Molt

WordNet (r) 3.0 (2006):

molt
    n 1: periodic shedding of the cuticle in arthropods or the outer
         skin in reptiles [syn: molt, molting, moult,
         moulting, ecdysis]
    v 1: cast off hair, skin, horn, or feathers; "our dog sheds
         every Spring" [syn: shed, molt, exuviate, moult,
         slough]