Source : Webster's Revised Unabridged Dictionary (1913)

Reckon \Reck"on\, v. t. [imp. & p. p. {Reckoned}; p. pr. & vb.
   n. {Reckoning}.] [OE. rekenen, AS. gerecenian to explain;
   akin to D. rekenen to reckon, G. rechnen, OHG. rahnjan), and
   to E. reck, rake an implement; the original sense probably
   being, to bring together, count together. See {Reck}, v. t.]
   1. To count; to enumerate; to number; also, to compute; to
      calculate.

            The priest shall reckon to him the money according
            to the years that remain.             --Lev. xxvii.
                                                  18.

            I reckoned above two hundred and fifty on the
            outside of the church.                --Addison.

   2. To count as in a number, rank, or series; to estimate by
      rank or quality; to place by estimation; to account; to
      esteem; to repute.

            He was reckoned among the transgressors. --Luke
                                                  xxii. 37.

            For him I reckon not in high estate.  --Milton.

   3. To charge, attribute, or adjudge to one, as having a
      certain quality or value.

            Faith was reckoned to Abraham for righteousness.
                                                  --Rom. iv. 9.

            Without her eccentricities being reckoned to her for
            a crime.                              --Hawthorne.

   4. To conclude, as by an enumeration and balancing of
      chances; hence, to think; to suppose; -- followed by an
      objective clause; as, I reckon he won't try that again.
      [Prov. Eng. & Colloq. U. S.]

   Syn: To number; enumerate; compute; calculate; estimate;
        value; esteem; account; repute. See {Calculate},
        {Guess}.

Reckoning \Reck"on*ing\, n.
   1. The act of one who reckons, counts, or computes; the
      result of reckoning or counting; calculation.
      Specifically:
      (a) An account of time. --Sandys.
      (b) Adjustment of claims and accounts; settlement of
          obligations, liabilities, etc.

                Even reckoning makes lasting friends, and the
                way to make reckonings even is to make them
                often.                            --South.

                He quitted London, never to return till the day
                of a terrible and memorable reckoning had
                arrived.                          --Macaulay.

   2. The charge or account made by a host at an inn.

            A coin would have a nobler use than to pay a
            reckoning.                            --Addison.

   3. Esteem; account; estimation.

            You make no further reckoning of it [beauty] than of
            an outward fading benefit nature bestowed. --Sir P.
                                                  Sidney.

   4. (Navigation)
      (a) The calculation of a ship's position, either from
          astronomical observations, or from the record of the
          courses steered and distances sailed as shown by
          compass and log, -- in the latter case called dead
          reckoning (see under {Dead}); -- also used fro dead
          reckoning in contradistinction to observation.
      (b) The position of a ship as determined by calculation.

   {To be out of her reckoning}, to be at a distance from the
      place indicated by the reckoning; -- said of a ship.

Source : WordNet®

reckoning
     n 1: problem solving that involves numbers or quantities [syn: {calculation},
           {computation}, {figuring}]
     2: a bill for an amount due [syn: {tally}]
     3: the act of counting; "the counting continued for several
        hours" [syn: {count}, {counting}, {numeration}, {enumeration},
         {tally}]