efficient
Americanadjective
-
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
-
satisfactory and economical to use.
Our new air conditioner is more efficient than our old one.
-
producing an effect, as a cause; causative.
-
utilizing a particular commodity or product with the least waste of resources or effort (usually used in combination).
a fuel-efficient engine.
adjective
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functioning or producing effectively and with the least waste of effort; competent
-
philosophy producing a direct effect; causative
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
Derived Forms
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
Explanation
The adjective efficient describes function and use with the least amount of waste and most economy. When you want to define the adjective efficient, it's a good idea to say as much as you can in as few words as possible because to be efficient is to be economical and avoid waste in actions or uses. The word comes from the Latin efficientem which means "work out" or "accomplish." Synonyms of efficient are effective, productive, and competent.
Vocabulary lists containing efficient
List 1
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Labor Day Lexicon: Words That Put You To Work
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Essential English Vocabulary, List 1
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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.
To be an efficient cushion for countries and companies, however, stockpiles need to be at “Goldilocks” levels: not too much, not too little.
From MarketWatch • Jun. 6, 2026
If successful, such systems could transform emergency oil spill response by converting ordinary fires into highly efficient cleanup tools.
From Science Daily • Jun. 5, 2026
In an earlier statement, Mather said the new laws would modernise UK aviation and support the redesign of airspace for faster, more efficient flights, while "enhancing aviation safety standards and delivering greater passenger protections".
From BBC • Jun. 3, 2026
The system boasts a physical-to-logical qubit ratio of 2:1, signaling a highly efficient error-correction code that bodes well for scaling to larger systems.
From Barron's • Jun. 3, 2026
Was it more efficient than using a lot of smaller bombs?
From "A Place to Belong" by Cynthia Kadohata
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
