efficient
Pluralefficients
- 1Working well without wasting time, energy, or other resources.
Like a car that goes far on just a little gas.
The new washing machine is very efficient and saves water.
She found an efficient way to clean the whole house quickly.
Similareconomical, productive, streamlined, organized, effective
Oppositeinefficient, wasteful, disorganized, unproductive
Note
- 2Using a large share of the energy put in, with very little wasted.
Like a cup that holds almost all the water you pour in, spilling barely any.
This heater is about ninety percent efficient, so little energy is lost.
Solar panels are getting more efficient every year.
Similareconomical
Oppositeinefficient, wasteful
Note
- 3Causing something to happen or making it come into being.
Like the spark that starts a fire: it's what makes the thing happen.
Many thinkers ask what the efficient cause of the universe might be.
The judge ruled that the broken brake was the efficient cause of the crash.
Note
- 4Able to produce the result that is wanted.
Like medicine that really makes you better.
The general found the new tactic efficient in breaking the siege.
The healer's tonic proved efficient against the fever.
Similareffective, efficacious, effectual, potent
Oppositeineffective, ineffectual, useless
Note
Less common meaning
- 5A thing or person that makes something else happen.
Like the push that starts a ball rolling.
The ancient teacher named heat the efficient of all growth.
Some held that the mind was the efficient of every deliberate act.
Note
Showing meanings only.
Practice
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Origin
From Latin efficere, meaning "to work out" or "accomplish." It first came into English in 1398 through Old French, and the sense "productive, skilled" appeared in 1787.