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

Keep scrolling for more

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.
See More
Recent Examples on the Web Two years ago, the company’s plan had been to improve its steelmaking efficiency and reduce emissions at its Mon Valley Works operations. Marc Levy, chicagotribune.com, "U.S. Steel drops plans for $1.5B revamp of Pennsylvania plants. ‘The world is changing rapidly.’," 30 Apr. 2021 Oil volume on Enbridge's Minnesota system rose steadily in the late 2010s, climbing past an annual average of more than 2.8 million barrels per day as the company increased its operating efficiency. Mike Hughlett, Star Tribune, "PUC won't review higher oil flow in Enbridge lines," 29 Apr. 2021 Streaming has catapulted the industry into handling trillions of micro-transactions, and while the onset of digitization imposed obvious technology costs, songwriters should have long ago started benefiting from its improved efficiency. Billboard, "Pay It Again, Sam: We Still Need New Publishing Infrastructure (Guest Op-Ed)," 29 Apr. 2021 For example, banks and credit unions focusing on business customers can increase fee revenue with products that improve their back-office efficiency. Arcady Lapiro, Forbes, "Three Key Lessons Community Banks And Credit Unions Can Learn From Challenger Banks," 28 Apr. 2021 Turnbull was encouraging in all aspects Wednesday, including his efficiency. Evan Petzold, Detroit Free Press, "Detroit Tigers' Spencer Turnbull turns it up in return for 5-2 win in Game 2 vs. Pirates," 22 Apr. 2021 The best silicon cells are approaching their theoretical maximum efficiency of about 29 percent. NBC News, "Solar panels are reaching their limit. These crystals could change that.," 19 Apr. 2021 But overall, his efficiency in making decisions was one. Tom Green | Tgreen@al.com, al, "What Bryan Harsin said about Auburn’s A-Day spring football game," 18 Apr. 2021 Raw power and potential who needs to improve his efficiency and understanding of the position. David Moore, Dallas News, "Pre-draft position preview: Antwaun Woods is dependable, but DT is far from Cowboys’ strength," 11 Apr. 2021

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.

See More

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

Keep scrolling for more

Learn More about efficiency

Time Traveler for efficiency

Time Traveler

The first known use of efficiency was in 1633

See more words from the same year

Statistics for efficiency

Last Updated

3 May 2021

Cite this Entry

“Efficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/efficiency. Accessed 12 May. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

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

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).


Test Your Vocabulary

Star Wars Words Quiz

  • cu jedi training
  • The bounty portion of bounty hunters (such as Boba Fett) comes from a Latin word meaning
Spell It

Can you spell these 10 commonly misspelled words?


Anagram puzzles meet word search.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!