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

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.
Recent Examples on the Web Equally satisfying to drive as be driven in, dripping with Old World charm but simultaneously boasting the modern efficiency and convenience of driver aids. Mark Phelan, Detroit Free Press, 4 Aug. 2022 The loops also boost the efficiency of adaptive signal timing systems San Diego has been adding to congested roads in recent years, Riveros said. David Garrick, San Diego Union-Tribune, 30 July 2022 These boats have an efficiency of 400%, and can cruise for 150 minutes before needing to recharge, say the company. Julia Buckley, CNN, 28 July 2022 During the height of the pandemic, for instance, Technion data scientists raced to improve the efficiency of PCR tests using algorithms. Larry Luxner, Sun Sentinel, 28 July 2022 Housing and Urban Development will also receive money to provide grants to improve the energy efficiency of low-income housing. John Timmer, Ars Technica, 28 July 2022 The improved method uses new surface treatments to increase the efficiency of heating and evaporating water. Joshua Hawkins, BGR, 21 July 2022 That all changed with today’s explosion of data and the irresistible efficiency of cloud apps, giving rise to entities such as European Union’s General Data Protection Regulation (GDPR) and California’s Consumer Privacy Act, to name just a few. Gavin Garbutt, Forbes, 19 July 2022 The ratings are based not solely on the efficiency of the building but also the sustainability of the materials used. Tim Fitzpatrick, The Salt Lake Tribune, 16 July 2022 See More

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.

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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Time Traveler for efficiency

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The first known use of efficiency was in 1633

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Last Updated

7 Aug 2022

Cite this Entry

“Efficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/efficiency. Accessed 11 Aug. 2022.

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More Definitions for efficiency


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

More from Merriam-Webster on efficiency

Nglish: Translation of efficiency for Spanish Speakers

Britannica English: Translation of efficiency for Arabic Speakers

Britannica.com: Encyclopedia article about efficiency


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