The Collaborative International Dictionary of English v.0.48:

Disposition \Dis`po*si"tion\, n. [F. disposition, dispositio,
   fr. disponere to dispose; dis- + ponere to place. See
   Position, and cf. Dispone.]
   1. The act of disposing, arranging, ordering, regulating, or
      transferring; application; disposal; as, the disposition
      of a man's property by will.
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            Who have received the law by the disposition of
            angels.                               --Acts vii.
                                                  53.
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            The disposition of the work, to put all things in a
            beautiful order and harmony, that the whole may be
            of a piece.                           --Dryden.
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   2. The state or the manner of being disposed or arranged;
      distribution; arrangement; order; as, the disposition of
      the trees in an orchard; the disposition of the several
      parts of an edifice.
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   3. Tendency to any action or state resulting from natural
      constitution; nature; quality; as, a disposition in plants
      to grow in a direction upward; a disposition in bodies to
      putrefaction.
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   4. Conscious inclination; propension or propensity.
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            How stands your disposition to be married? --Shak.
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   5. Natural or prevailing spirit, or temperament of mind,
      especially as shown in intercourse with one's fellow-men;
      temper of mind. "A man of turbulent disposition."
      --Hallam. "He is of a very melancholy disposition."
      --Shak.
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            His disposition led him to do things agreeable to
            his quality and condition wherein God had placed
            him.                                  --Strype.
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   6. Mood; humor.
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            As I perchance hereafter shall think meet
            To put an antic disposition on.       --Shak.

   Syn: Disposal; adjustment; regulation; arrangement;
        distribution; order; method; adaptation; inclination;
        propensity; bestowment; alienation; character; temper;
        mood. -- Disposition, Character, Temper.
        Disposition is the natural humor of a person, the
        predominating quality of his character, the
        constitutional habit of his mind. Character is this
        disposition influenced by motive, training, and will.
        Temper is a quality of the fiber of character, and is
        displayed chiefly when the emotions, especially the
        passions, are aroused.
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WordNet (r) 3.0 (2006):

disposition
    n 1: your usual mood; "he has a happy disposition" [syn:
         disposition, temperament]
    2: the act or means of getting rid of something [syn:
       disposal, disposition]
    3: an attitude of mind especially one that favors one
       alternative over others; "he had an inclination to give up
       too easily"; "a tendency to be too strict" [syn:
       inclination, disposition, tendency]
    4: a natural or acquired habit or characteristic tendency in a
       person or thing; "a swelling with a disposition to rupture"