The Collaborative International Dictionary of English v.0.48:

Original \O*rig"i*nal\, n. [Cf. F. original.]
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   1. Origin; commencement; source.
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            It hath it original from much grief.  --Shak.
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            And spangled heavens, a shining frame,
            Their great Original proclaim.        --Addison.
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   2. That which precedes all others of its class; archetype;
      first copy; hence, an original work of art, manuscript,
      text, and the like, as distinguished from a copy,
      translation, etc.
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            The Scriptures may be now read in their own
            original.                             --Milton.
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   3. An original thinker or writer; an originator. [R.]
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            Men who are bad at copying, yet are good originals.
                                                  --C. G.
                                                  Leland.
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   4. A person of marked eccentricity. [Colloq.]
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   5. (Zool. & Bot.) The natural or wild species from which a
      domesticated or cultivated variety has been derived; as,
      the wolf is thought by some to be the original of the dog,
      the blackthorn the original of the plum.
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The Collaborative International Dictionary of English v.0.48:

Original \O*rig"i*nal\, a. [F. original, L. originalis.]
   [1913 Webster]
   1. Pertaining to the origin or beginning; preceding all
      others; first in order; primitive; primary; pristine; as,
      the original state of man; the original laws of a country;
      the original inventor of a process.
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            His form had yet not lost
            All her original brightness.          --Milton.
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   2. Not copied, imitated, or translated; new; fresh; genuine;
      as, an original thought; an original process; the original
      text of Scripture.
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   3. Having the power to suggest new thoughts or combinations
      of thought; inventive; as, an original genius.
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   4. Before unused or unknown; new; as, a book full of original
      matter.
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   Original sin (Theol.), the first sin of Adam, as related to
      its consequences to his descendants of the human race; --
      called also total depravity. See Calvinism.
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WordNet (r) 3.0 (2006):

original
    adj 1: preceding all others in time or being as first made or
           performed; "the original inhabitants of the Americas";
           "the book still has its original binding"; "restored the
           house to its original condition"; "the original
           performance of the opera"; "the original cast";
           "retracted his original statement"
    2: (of e.g. information) not secondhand or by way of something
       intermediary; "his work is based on only original, not
       secondary, sources"
    3: being or productive of something fresh and unusual; or being
       as first made or thought of; "a truly original approach";
       "with original music"; "an original mind" [ant: unoriginal]
    4: not derived or copied or translated from something else; "the
       play is original; not an adaptation"; "he kept the original
       copy and gave her only a xerox"; "the translation misses much
       of the subtlety of the original French"
    n 1: an original creation (i.e., an audio recording) from which
         copies can be made [syn: master, master copy,
         original]
    2: something that serves as a model or a basis for making
       copies; "this painting is a copy of the original" [syn:
       original, archetype, pilot]