ENGLISH
REFERENCE

efficiency

n. uncountable
C1 Advanced Oxford US //ɪˈfɪʃənsi// UK //ɪfˈɪʃənsi// ef·fi·cien·cy Archaic

n. the ability to do something well without wasting time, money, or energy. You use this to describe a person or machine that gets a lot done with very little waste.

n. the state or quality of achieving maximum productivity with minimum wasted effort or expense. Often used in technical or economic contexts to describe the ratio of useful output to total input.


SIMPLE

The new engine has much better fuel efficiency.

CONTEXTUAL

The manager introduced a new software system to improve the efficiency of the office and reduce paper waste.

COMPLEX

While the factory's mechanical efficiency is high, the overall profitability remains low due to the rising costs of raw materials and international shipping logistics.

Antonyms
Origin

From Latin efficientia, equivalent to efficient + -cy.

Usage

Often modified by adjectives like 'energy', 'fuel', or 'operational'.

Pitfall

He works with a lot of efficientHe works with a lot of efficiencyLearners often use the adjective 'efficient' when the noun 'efficiency' is required after a preposition or quantifier.

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