noun \i-ˈfi-shən-sē\

: the ability to do something or produce something without wasting materials, time, or energy : the quality or degree of being efficient ( technical )

plural ef·fi·cien·cies

Full Definition of EFFICIENCY

:  the quality or degree of being efficient
a :  efficient operation
b (1) :  effective operation as measured by a comparison of production with cost (as in energy, time, and money)
(2) :  the ratio of the useful energy delivered by a dynamic system to the energy supplied to it

Examples of EFFICIENCY

  1. Because of her efficiency, we got all the work done in a few hours.
  2. The factory was operating at peak efficiency.
  3. A furnace with 80 percent fuel efficiency wastes 20 percent of its fuel.
  4. The company is trying to lower costs and improve efficiencies.

First Known Use of EFFICIENCY



noun    (Concise Encyclopedia)

In mechanics, the measure of the effectiveness with which a system performs. It is stated as the ratio of a system's work output to its work input. The efficiency of a real system is always less than 1 because of friction between moving parts. A machine with an efficiency of 0.8 returns 80% of the work input as work output; the remaining 20% is used to overcome friction. In a theoretically frictionless, or ideal, machine, the work input and work output are equal, and the efficiency would be 1, or 100%.

Variants of EFFICIENCY

efficiency or mechanical efficiency


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