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Synonyms

efficient

American  
[ih-fish-uhnt] / ɪˈfɪʃ ənt /

adjective

  1. performing or functioning in the best possible manner with the least waste of time and effort; having and using requisite knowledge, skill, and industry; competent; capable.

    a reliable, efficient assistant.

    Synonyms:
    effectual
  2. satisfactory and economical to use.

    Our new air conditioner is more efficient than our old one.

  3. producing an effect, as a cause; causative.

  4. utilizing a particular commodity or product with the least waste of resources or effort (usually used in combination).

    a fuel-efficient engine.


efficient British  
/ ɪˈfɪʃənt /

adjective

  1. functioning or producing effectively and with the least waste of effort; competent

  2. philosophy producing a direct effect; causative

"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

Usage

What are other ways to say efficient? A person or a thing that is efficient performs or functions in the best possible manner with the least waste of time and effort. But efficient isn’t quite the same as effectual, efficacious, or effective! Find out why on Thesaurus.com. 

Other Word Forms

  • efficiently adverb
  • nonefficient adjective
  • quasi-efficient adjective
  • superefficient adjective
  • unefficient adjective

Etymology

Origin of efficient

First recorded in 1350–1400; Middle English, from Middle French, from Latin efficient- (stem of efficiēns ), equivalent to ef- ef- + fic-, combining form of facere “to make, do 1 ” + -ent- -ent

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

American dairy operations are large and efficient, with generations of experience making European-style cheeses, so they can sometimes offer better prices than European rivals.

From The Wall Street Journal • Apr. 6, 2026

Magyar's promise to build "a more humane, efficient country" resonates with all those fed up with the governing party, especially the young.

From BBC • Apr. 3, 2026

But like that first rout, Thursday’s featured a flurry of Lakers turnovers, suffocating Oklahoma City ball pressure and an efficient masterclass from Shai Gilgeous-Alexander.

From Los Angeles Times • Apr. 3, 2026

The optical wireless system uses laser sources that are inherently energy efficient and capable of high-speed operation without complex power demands.

From Science Daily • Apr. 2, 2026

Since you can exert more force pulling and pushing on a lever than you can turning a crank, this is more efficient than a crank mechanism would be at lifting weights.

From "The Invention of Science" by David Wootton