The Collaborative International Dictionary of English v.0.48:

Probable \Prob"a*ble\, a. [L. probabilis, fr. probare to try,
   approve, prove: cf. F. probable. See Prove, and cf.
   Provable.]
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   1. Capable of being proved. [Obs.]
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   2. Having more evidence for than against; supported by
      evidence which inclines the mind to believe, but leaves
      some room for doubt; likely.
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            That is accounted probable which has better
            arguments producible for it than can be brought
            against it.                           --South.
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            I do not say that the principles of religion are
            merely probable; I have before asserted them to be
            morally certain.                      --Bp. Wilkins.
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   3. Rendering probable; supporting, or giving ground for,
      belief, but not demonstrating; as, probable evidence;
      probable presumption. --Blackstone.
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   Probable cause (Law), a reasonable ground of presumption
      that a charge is, or my be, well founded.

   Probable error (of an observation, or of the mean of a
      number), that within which, taken positively and
      negatively, there is an even chance that the real error
      shall lie. Thus, if 3[sec] is the probable error in a
      given case, the chances that the real error is greater
      than 3[sec] are equal to the chances that it is less. The
      probable error is computed from the observations made, and
      is used to express their degree of accuracy.

   The probable, that which is within the bounds of
      probability; that which is not unnatural or preternatural;
      -- opposed to the marvelous.
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The Collaborative International Dictionary of English v.0.48:

Error \Er"ror\, n. [OF. error, errur, F. erreur, L. error, fr.
   errare to err. See Err.]
   1. A wandering; a roving or irregular course. [Obs.]
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            The rest of his journey, his error by sea. --B.
                                                  Jonson.
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   2. A wandering or deviation from the right course or
      standard; irregularity; mistake; inaccuracy; something
      made wrong or left wrong; as, an error in writing or in
      printing; a clerical error.
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   3. A departing or deviation from the truth; falsity; false
      notion; wrong opinion; mistake; misapprehension.
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            His judgment was often in error, though his candor
            remained unimpaired.                  --Bancroft.
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   4. A moral offense; violation of duty; a sin or
      transgression; iniquity; fault. --Ps. xix. 12.
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   5. (Math.) The difference between the approximate result and
      the true result; -- used particularly in the rule of
      double position.
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   6. (Mensuration)
      (a) The difference between an observed value and the true
          value of a quantity.
      (b) The difference between the observed value of a
          quantity and that which is taken or computed to be the
          true value; -- sometimes called residual error.
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   7. (Law.) A mistake in the proceedings of a court of record
      in matters of law or of fact.
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   8. (Baseball) A fault of a player of the side in the field
      which results in failure to put out a player on the other
      side, or gives him an unearned base.
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   Law of error, or Law of frequency of error (Mensuration),
      the law which expresses the relation between the magnitude
      of an error and the frequency with which that error will
      be committed in making a large number of careful
      measurements of a quantity.

   Probable error. (Mensuration) See under Probable.

   Writ of error (Law), an original writ, which lies after
      judgment in an action at law, in a court of record, to
      correct some alleged error in the proceedings, or in the
      judgment of the court. --Bouvier. Burrill.

   Syn: Mistake; fault; blunder; failure; fallacy; delusion;
        hallucination; sin. See Blunder.
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