{ Ef*fi"cience (?), Ef*fi"cien*cy (?), }
n. [L. efficientia.] 1.The quality of being efficient or producing an effect or
effects; efficient power; effectual agency.
The manner of this divine efficiency being far
above us.
Hooker.
2.(Mech.)The ratio of useful work to
energy expended.Rankine.
Efficiency of a heat engine, the ratio of
the work done by an engine, to the work due to the heat supplied to
it.