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effective

[ih-fek-tiv] /ɪˈfɛk tɪv/
adjective
1.
adequate to accomplish a purpose; producing the intended or expected result:
effective teaching methods; effective steps toward peace.
2.
actually in operation or in force; functioning:
The law becomes effective at midnight.
3.
producing a deep or vivid impression; striking:
an effective photograph.
4.
prepared and available for service, especially military service.
noun
5.
a member of the armed forces fit for duty or active service.
6.
the effective total of a military force.
Origin
1350-1400
1350-1400; Middle English < Latin effectīvus practical, equivalent to effect(us), past participle of efficere (see effect) + -īvus -ive
Related forms
effectively, adverb
effectiveness, effectivity, noun
preeffective, adjective
preeffectively, adverb
quasi-effective, adjective
quasi-effectively, adverb
subeffective, adjective
subeffectively, adverb
subeffectiveness, noun
supereffective, adjective
supereffectively, adverb
supereffectiveness, noun
uneffective, adjective
uneffectively, adverb
uneffectiveness, noun
Can be confused
affective, effective (see synonym study at the current entry)
Synonyms
1. capable, competent. Effective, effectual, efficacious, efficient refer to that which is able to produce a (desired) effect. Effective is applied to that which has the power to, or which actually does, produce an effect: an effective action, remedy, speech. Effectual is used especially of that which produces the effect desired or intended, or a decisive result: An effectual bombardment silenced the enemy. Efficacious suggests the capability of achieving a certain end: an efficacious plan, medicine. Efficient (applied also to persons) implies the skillful use of energy or industry to accomplish desired results with little waste of effort: efficient methods; an efficient manager. 2. operative. 3. telling.
Antonyms
1. futile, useless.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples from the web for effectiveness
  • Fewer than a third of these prescriptions were supported by strong evidence of effectiveness.
  • Most studies he's seen show no difference in the effectiveness of the two media.
  • In sum, there are solid grounds to be sceptical about the effectiveness of across-the-board capital controls.
  • Mud and other floating matter can detract from this method's effectiveness.
  • It still is, but a new repellent comes close in effectiveness.
  • All have been highly praised for their effectiveness.
  • Um, you need good information about which medical interventions work, and how well they work: comparative effectiveness research.
  • He highly recommends light therapy and says the research supports its effectiveness.
  • But advertisers also need to be able to measure the effectiveness of their campaigns.
  • Several drugs help to wean cocaine addicts from their physical dependency, but the compounds are limited in effectiveness.
British Dictionary definitions for effectiveness

effective

/ɪˈfɛktɪv/
adjective
1.
productive of or capable of producing a result
2.
in effect; operative: effective from midnight
3.
producing a striking impression; impressive: an effective entrance
4.
(prenominal) actual rather than theoretical; real: the effective income after deductions
5.
(of a military force, etc) equipped and prepared for action
6.
(physics) (of an alternating quantity) having a value that is the square root of the mean of the squares of the magnitude measured at each instant over a defined period of time, usually one cycle See also root mean square
noun
7.
a serviceman who is equipped and prepared for action
Derived Forms
effectively, adverb
effectiveness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for effectiveness
n.

c.1600, from effective + -ness.

effective

adj.

late 14c., from French effectif, from Latin effectivus "productive, effective," from effect-, stem of efficere (see effect (n.)). Effectively in the sense of "actually" is attested by 1650s. Related: Effectivity.

Online Etymology Dictionary, © 2010 Douglas Harper
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