ENGLISH
REFERENCE

efficient

adj.
B2 Upper Intermediate Oxford US //ɪˈfɪʃənt// UK //ɪfˈɪʃənt// ef·fi·cient Archaic General-service

adj. working in a way that gets good results without wasting time, energy, or money. You use this to describe people or machines that do a job well and quickly.

adj. achieving maximum productivity with minimum wasted effort or expense. Often used to describe systems, processes, or individuals that perform tasks competently and with little friction.


SIMPLE

The new heating system is much more efficient.

CONTEXTUAL

The manager introduced an efficient new filing system that reduced the time spent on paperwork by half.

COMPLEX

Modern logistics companies rely on highly efficient algorithms to determine the most fuel-effective routes, ensuring that thousands of packages reach their destinations with minimal environmental impact.

Synonyms
Antonyms
Origin

1398, “making,” from Old French, from Latin efficientem, nominative efficiēns, participle of efficere (“work out, accomplish”) (see effect). Meaning “productive, skilled” is from 1787. Efficiency apartment is first recorded 1930, American English.

Usage

Typically used to modify nouns or as a subject complement after linking verbs like 'be' or 'become'.

Pitfall

He is very effective at saving timeHe is very efficient at saving timeLearners confuse 'efficient' (doing things without waste) with 'effective' (producing the intended result).

© 2026 English Reference