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
-
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
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
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Labor Day Lexicon: Words That Put You To Work
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Essential English Vocabulary, List 1
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
A turbo engine is not only arguably more road-relevant, but is also more efficient than a naturally aspirated one, which means less fuel, even if turbos and their associated architecture are heavy and complicated.
From BBC • May 14, 2026
They described this highly efficient range as a "Goldilocks zone."
From Science Daily • May 14, 2026
Ultimately, the best protection against oil price shocks is a more efficient gas-burning vehicle, or one that doesn’t burn gasoline at all.
From Salon • May 13, 2026
The reason individual stock-picking is so dangerous is that if you believe markets are even somewhat efficient over the long run, you have to ask yourself what you know that the experts don’t.
From MarketWatch • May 12, 2026
The market was paying Goldman Sachs bond traders to make the market less efficient.
From "The Big Short" by Michael Lewis
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.
