[1] : The Collaborative International Dictionary of English v.0.48

reckoner \reck"oner\ re^k"'n~er, n.
   one who reckons or computes; also, a book of calculations,
   tables, etc., to assist in reckoning.
   1913 webster

         reckoners without their host must reckon twice.
                                                  --camden.
   1913 webster

[2] : WordNet (r) 2.0

reckoner
     n 1: an expert at calculation or at operating calculating
          machines syn: calculator, figurer, estimator, computer
     2: a handbook of tables used to facilitate computation syn: ready
        reckoner
see also:
calculator figurer estimator computer ready reckoner 

Reckoner >> R Words
Reckoner, definition of term: Reckoner
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