[ ih-fish-uhn-see ]
/ ɪˈfɪʃ ən si /
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See synonyms for: efficiency / efficiencies on Thesaurus.com

noun, plural ef·fi·cien·cies.

the state or quality of being efficient, or able to accomplish something with the least waste of time and effort; competency in performance.
accomplishment of or ability to accomplish a job with a minimum expenditure of time and effort: The assembly line increased industry's efficiency.
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.



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On the farm, the feed for chicks is significantly different from the roosters’; ______ not even comparable.

Origin of efficiency

1585–95; <Latin efficientia, equivalent to efficient- (see efficient) + -ia-y3
non·ef·fi·cien·cy, nounsu·per·ef·fi·cien·cy, noun, plural su·per·ef·fi·cien·cies.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for efficiency

/ (ɪˈfɪʃənsɪ) /

noun plural -cies

the quality or state of being efficient; competence; effectiveness
the ratio of the useful work done by a machine, engine, device, etc, to the energy supplied to it, often expressed as a percentageSee 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

Medical definitions for efficiency

[ ĭ-fĭshən-sē ]


The production of the desired effects or results with minimum waste of time, effort, or skill.
A measure of effectiveness; specifically, the useful work output divided by the energy input in any system.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for efficiency

[ ĭ-fĭshən-sē ]

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. See also mechanical advantage.
The ratio of the effective or useful output to the total input in any system.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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