adjective

inefficient

ihn-ih-FIHSH-uhnt

adjective

Not making good use of time, energy, or resources; wasteful.

"The old boiler is inefficient and burns far more gas than a modern one."

"Manually copying data between spreadsheets is slow and inefficient."

Not able to work productively; sluggish or unproductive.

"An inefficient team can drag out a simple project for weeks."

How to Use Inefficient

Learner’s notes

In plain EnglishWasting resources to get a result — the opposite of doing something the smart, economical way.

Easily confused with

ineffective →

Common pairings

inefficient use of energy-inefficient grossly inefficient

more inefficient comparative, inefficients plural, most inefficient superlative

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Can you complete this real example?

The old boiler is _____ and burns far more gas than a modern one.

From in- + efficient, from Latin efficientem, "effective, powerful."

efficient

feckless efficient

orient ancient patient salient ambient lenient obedient nutrient gradient sentient impatient transient

efficient feckless