The Collaborative International Dictionary of English v.0.48:

Litter \Lit"ter\, v. t. [imp. & p. p. Littered
   (l[i^]t"t[~e]rd); p. pr. & vb. n. Littering.]
   1. To supply with litter, as cattle; to cover with litter, as
      the floor of a stall.
      [1913 Webster]

            Tell them how they litter their jades. --Bp.
                                                  Hackett.
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            For his ease, well littered was the floor. --Dryden.
      [1913 Webster]

   2. To put into a confused or disordered condition; to strew
      with scattered articles; as, to litter a room.
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            The room with volumes littered round. --Swift.
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   3. To give birth to; to bear; -- said of brutes, esp. those
      which produce more than one at a birth, and also of human
      beings, in abhorrence or contempt.
      [1913 Webster]

            We might conceive that dogs were created blind,
            because we observe they were littered so with us.
                                                  --Sir T.
                                                  Browne.
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            The son that she did litter here,
            A freckled whelp hagborn.             --Shak.
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The Collaborative International Dictionary of English v.0.48:

littered \lit"tered\ (l[i^]t"t[~e]rd), adj.
   having articles scattered about in a disorderly fashion.

   Syn: cluttered, messy, mussy, untidy.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

littered
    adj 1: filled or scattered with a disorderly accumulation of
           objects or rubbish; "the storm left the drivewaylittered
           with sticks nd debris"; "his library was a cluttered room
           with piles of books on every chair" [syn: cluttered,
           littered]