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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 for effective
  • Recently it did some research on the effective formation of memories.
  • More studies will be required to see if the vaccine can be made more effective and translated to other strains of the virus.
  • Over all, the mop was effective, except on very wet spills.
  • The thick black smoke was such an effective warning signal that to this day the Chinese phrase "wolf smoke" means crisis.
  • The first step to building an effective corporate philanthropic program is to determine the design and structure.
  • Human hunters have been less effective at keeping down the deer population.
  • It looks like the habits of highly effective people are indeed hard to break—when it comes to audiobooks, that is.
  • The brain is like a muscle: when it gets depleted, it becomes less effective.
  • It's a very simple an effective way to check the water level.
  • What made him especially effective was his ability to catch passes out of the backfield.
British Dictionary definitions for effective

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 effective
effective
late 14c., from Fr. effectif, from L. effectivus (see effect). Related: Effectively; effectivity.
Online Etymology Dictionary, © 2010 Douglas Harper
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