from
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