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Synonyms

efficiency

American  
[ih-fish-uhn-see] / ɪˈfɪʃ ən si /

noun

plural

efficiencies
  1. the state or quality of being efficient, or able to accomplish something with the least waste of time and effort; competency in performance.

  2. accomplishment of or ability to accomplish a job with a minimum expenditure of time and effort.

    The assembly line increased industry's efficiency.

  3. the ratio of the work done or energy developed by a machine, engine, etc., to the energy supplied to it, usually expressed as a percentage.

  4. efficiency apartment.


efficiency British  
/ ɪˈfɪʃənsɪ /

noun

  1. the quality or state of being efficient; competence; effectiveness

  2. the ratio of the useful work done by a machine, engine, device, etc, to the energy supplied to it, often expressed as a percentage See also thermal efficiency

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

efficiency Scientific  
/ ĭ-fĭshən-sē /
  1. The ratio of the energy delivered (or work done) by a machine to the energy needed (or work required) in operating the machine. The efficiency of any machine is always less than one due to forces such as friction that use up energy unproductively.

  2. See also mechanical advantage

  3. The ratio of the effective or useful output to the total input in any system.


Other Word Forms

  • nonefficiency noun
  • superefficiency noun

Etymology

Origin of efficiency

First recorded in 1585–95; from Latin efficientia, from efficient- (stem of efficiēns efficient ) + -ia -y 3