from
The Collaborative International Dictionary of English v.0.48
efficience \ef*fi"cience\ ([e^]f*f[i^]sh"ens), efficiency
\ef*fi"cien*cy\ ([e^]f*f[i^]sh"en*s[y^]), n. [L. efficientia.]
1. The quality of being efficient or producing an effect or
effects; efficient power; effectual agency.
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The manner of this divine efficiency being far above
us. --Hooker.
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2. (Mech.) The ratio of useful work to energy expended.
--Rankine.
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{efficiency of a heat engine}, the ratio of the work done by
an engine, to the work due to the heat supplied to it.
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