ef·​fi·​cien·​cy | \ i-ˈfi-shən-sē How to pronounce efficiency (audio) \
plural efficiencies

Definition of efficiency

1 : the quality or degree of being efficient
2a : 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

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Examples of efficiency in a Sentence

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

His departure seemed to be handled with efficiency... Nicole Phelps, Vogue, "Constant Innovation in a Culture of Inclusivity: A Conversation With Tapestry CEO Victor Luis," 30 Jan. 2019 Blue light generates infrared light with an efficiency of about 180 percent. Chris Lee, Ars Technica, "Transparent solar cell turns edge on and generates its own light," 12 Dec. 2018 Some economists like to think that if each energy source and service were priced properly, based on its real-time, location-specific value, the market would allocate electricity with perfect efficiency. David Roberts, Vox, "Clean energy technologies threaten to overwhelm the grid. Here’s how it can adapt.," 30 Nov. 2018 Meanwhile, the company wants production to continue with maximum efficiency. Julia M. Klein, Philly.com, "'Skeleton Crew' at People's Light: Human relations in the workplace during the great recession," 18 June 2018 Tuesday's operation was carried out with quiet efficiency. Bloomberg.com, "Immigration Agents Arrest 114 in Landscaper Sting," 5 June 2018 Silver sailed through his news conference with customary efficiency. Ron Kroichick, Houston Chronicle, "NBA commissioner Adam Silver: No anthem policy alterations needed," 1 June 2018 The Trump administration, which has been critical of the efficiency of these groups, has reshaped the Obama-era program to operate with limited resources, according to a HHS draft rule. Ken Alltucker, USA TODAY, "Obamacare: Outreach groups nervous as Trump remains silent on funding," 21 June 2018 For several years, a balance was preserved between commerce and art—or, really, between a standardized production process in search of efficiencies of scale, and creative individuality. Stephen Metcalf, The New Yorker, "How Superheroes Made Movie Stars Expendable," 19 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'efficiency.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of efficiency

1633, in the meaning defined at sense 1

History and Etymology for efficiency

borrowed from Latin efficientia, from efficient-, efficiens "producing or giving rise to something, immediate (of a cause), efficient" + -ia -y entry 2

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Statistics for efficiency

Last Updated

9 May 2019

Look-up Popularity

Time Traveler for efficiency

The first known use of efficiency was in 1633

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More Definitions for efficiency



English Language Learners Definition of efficiency

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


ef·​fi·​cien·​cy | \ i-ˈfi-shən-sē How to pronounce efficiency (audio) \
plural efficiencies

Kids Definition of efficiency

: the ability to do something or produce something without waste

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Comments on efficiency

What made you want to look up efficiency? Please tell us where you read or heard it (including the quote, if possible).


a sum of money that is sent as a payment

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