Definitions

efficiency

[ih-fish-uhn-see] / ɪˈfɪʃ ən si /

NOUN

adeptness, effectiveness

Synonyms

STRONGEST

ability adaptability capability competence energy expertise performance productivity readiness skill talent

STRONG

abundance address adequacy capableness competency completeness economy effectualness efficacy facility faculty know-how potency power powerfulness productiveness proficiency prowess quantity resourcefulness response skillfulness suitability suitableness thoroughness

Antonyms

STRONGEST

idleness ignorance impotence inability inadequacy incapability incapacity incompetence ineptness weakness

STRONG

inefficiency lack

WEAK

helplessness ineffectiveness

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.

Other jets use “bleed” air from the engines, which reduces fuel efficiency.

From Barron's • Jun. 8, 2026

On Friday, they made 15 3-pointers to the Spurs’ 11, while shooting a higher efficiency from beyond the arc.

From The Wall Street Journal • Jun. 7, 2026

Such flexibility could improve coverage, strengthen reliability, and increase operational efficiency.

From Science Daily • Jun. 6, 2026

Similar questions have emerged in other policy areas where institutions have moved toward consolidation of identity categories in the name of efficiency.

From Salon • Jun. 6, 2026

She had done the deed with credible efficiency.

From "Genuine Fraud" by E. Lockhart

Vocabulary lists containing efficiency

Word Generation Science - Energy

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!

"The Veldt" by Ray Bradbury

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!

The Boy in the Striped Pajamas

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!