different between efficiency vs effective

English

Etymology

From Latin efficientia.

Pronunciation

• IPA^(key): /??f??n?si/

Noun

efficiency (countable and uncountable, plural efficiencies)

1. The extent to which time is well used for the intended task.

   Antonyms: inefficiency, wastefulness
2. (dated) The quality of producing an effect or effects.
   • 1594, Richard Hooker, Of the Lawes of Ecclesiastical Politie

     The manner of this divine efficiency being far above us.

3. The extent to which a resource, such as electricity, is used for the intended purpose; the ratio of useful work to energy expended.

   Antonyms: inefficiency, wastefulness

4. (US) A one-room apartment.

   Synonyms: efficiency apartment, (UK, Ireland) bedsit

Hyponyms

Derived terms

Related terms

Translations

References

• efficiency on Wikipedia.Wikipedia

English

Etymology

From French effectif, from Latin effect?vus (“productive; effective”), from effici? (“I make; I bring about”).

Pronunciation

• (weak vowel distinction) IPA^(key): /??f?kt?v/
• (weak vowel merger) IPA^(key): /??f?kt?v/
• Rhymes: -?kt?v

Adjective

effective (comparative more effective, superlative most effective)

1. Having the power to produce a required effect or effects.

   Synonym: efficacious

2. Producing a decided or decisive effect.
   • 1650, Jeremy Taylor, The Rule and Exercises of Holy Living

     Whosoever is an effective, real cause of doing his neighbour wrong, is criminal.

3. Efficient, serviceable, or operative, available for useful work.

4. Actually in effect.

5. (geometry, of a cycle or divisor) Having no negative coefficients.
6. (physics, for any effective theory) approximate; Not describing the fundamental dynamic changes in some system as they happen.

Usage notes

Webster's Revised Unabridged Dictionary from 1913 still lists efficient and effective as synonyms, but all major dictionaries now show that these words now only have different meanings in careful use. Use of both for the other meaning is however widespread enough that Longman's Exam Dictionary, for example, finds it necessary to proscribe the use of one for the other with several examples at each entry and provides the following summary:

• efficient = working quickly and without waste
• effective = having the desired effect

Related terms

Translations

Noun

effective (plural effectives)

1. (military) a soldier fit for duty
   • 1876, Dabney Herndon Maury, Southern Historical Society Papers: Volume 2, Number 4, Recollections of the Elkhorn Campaign:

     The Army of the West reached Corinth sometime after the battle of Shiloh. We were 15,000 effectives, and brought Beauregard's effective force up to 45,000 men.

French

Pronunciation

• IPA^(key): /e.f?k.tiv/
• Homophone: effectives

Adjective

effective

1. feminine singular of effectif

Latin

Adjective

effect?ve

1. vocative masculine singular of effect?vus