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

efficience \effi"cience\ e^ffi^sh"ens, efficiency
\effi"ciency\ e^ffi^sh"ensy^, n. l. efficientia.
   1. the quality of being efficient or producing an effect or
      effects; efficient power; effectual agency.
      1913 webster

            the manner of this divine efficiency being far above
            us.                                   --hooker.
      1913 webster

   2. mech. the ratio of useful work to energy expended.
      --rankine.
      1913 webster

   efficiency of a heat engine, the ratio of the work done by
      an engine, to the work due to the heat supplied to it.
      1913 webster
see also:
efficiency of a heat engine 

Efficience >> E Words
Efficience, definition of term: Efficience
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