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a. Having an intended or expected effect.
b. Producing a strong impression or response; striking: gave an effective performance as Othello.
2. Operative; in effect: The law is effective immediately.
3. Existing in fact; actual: a decline in the effective demand.
4. Prepared for use or action, especially in combat.
A soldier or a piece of military equipment that is ready for combat.

ef·fec′tive·ness, ef′fec·tiv′i·ty n.
Synonyms: effective, effectual, efficacious
These adjectives mean producing or capable of producing a desired effect: an effective reprimand; an effectual complaint; an efficacious remedy.



blockbuster Something extremely forceful, violent, or effective; a success, a winner, a hit. The term owes its origin to the name given the highly destructive bombs dropped on industrial targets in Britain during World War II.

corker A clincher or a sockdolager, something that settles the question or closes the discussion; also, a lollapalooza; something striking, astonishing, or extraordinary. In use since 1837, this slang term probably derives from the image of a cork “capping a bottle” (the first three meanings) or flying off a champagne bottle with a bang (the latter meanings). Corker was also a baseball term in the late 19th century.

haymaker Any extremely forceful or effective argument, statement, ploy, maneuver, etc., especially a decisive and culminating one. The term is boxing slang for a violent punch or knockout blow. Hay is grass or alfalfa which has been cut or mowed down. Similarly, the recipient of a haymaker in a pugilistic encounter is “cut down.” Mow (someone) down is a related expression.

I deliberately pulled my right back and swung “haymakers” at Choinyski, intending to miss him. (J. J. Corbett, Roar of the Crowd, 1925)

the old one-two Any especially effective combination of two persons or things; a double whammy. The reference is to boxing and the highly effective combination punch consisting of a left jab immediately followed by a hard right cross, usually to the opponent’s jaw and intended as a knockout blow.

put teeth into To make effective or enforceable; to give meaning or substance to. Webster’s Third cites a contemporary use by E. O. Hauser:

… started turning out the arms which would put teeth into neutrality.

The expression is most often used with reference to legislation.

sledge-hammer argument A single statement or ploy which completely dissolves the opposition in a disagreement; a clincher. A sledge-hammer is a large, weighty hammer which, if used as a weapon, can easily incapacitate the victim. This expression is heard infrequently today.

ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.effectiveness - power to be effective; the quality of being able to bring about an effect
power, powerfulness - possession of controlling influence; "the deterrent power of nuclear weapons"; "the power of his love saved her"; "his powerfulness was concealed by a gentle facade"
incisiveness, trenchancy - keenness and forcefulness of thought or expression or intellect
efficaciousness, efficacy - capacity or power to produce a desired effect; "concern about the safety and efficacy of the vaccine"
ineffectiveness, ineffectuality, ineffectualness - lacking the power to be effective
2.effectiveness - capacity to produce strong physiological or chemical effects; "the toxin's potency"; "the strength of the drinks"
power, powerfulness - possession of controlling influence; "the deterrent power of nuclear weapons"; "the power of his love saved her"; "his powerfulness was concealed by a gentle facade"


noun power, effect, efficiency, success, strength, capability, use, validity, usefulness, potency, efficacy, fruitfulness, productiveness the effectiveness of computers as an educational tool


The power or capacity to produce a desired result:


[ɪˈfektɪvnɪs] N
1. (= efficiency) [of method, system] → eficacia f, eficiencia f; [of treatment, deterrent, argument] → eficacia f
2. (= striking quality) → efecto m


[ɪˈfɛktɪvnɪs] n [action, method] → efficacité f


(= successfulness)Wirksamkeit f; (of strategy, government, politician)Effektivität f
(= striking effect)Wirkung f


[ɪˈfɛktɪvnɪs] nefficacia


n. eficacia, efectividad.


n eficacia, efectividad f; (clinical research) eficacia bajo condiciones normales (See note under efficacy.)
References in classic literature ?
To those monks that pump was a good deal of a miracle itself, and they were full of wonder over it; and of admiration, too, of the exceeding effectiveness of its performance.
The trainer was not slow to note the boy's handsome, eager face, and as one of Ajax's biggest hits consisted in an entry to one or more boxes during his performance, ostensibly in search of a long-lost relative, as the trainer explained, the man realized the effectiveness of sending him into the box with the handsome boy, who, doubtless, would be terror stricken by proximity to the shaggy, powerful beast.
Madame Urbain meanwhile had seized her little girl by the hand, with a gesture of surprise and impatience which struck Newman, intent as he was upon his own words, with its dramatic effectiveness.
For he had been as instructive as Milton's "affable archangel;" and with something of the archangelic manner he told her how he had undertaken to show (what indeed had been attempted before, but not with that thoroughness, justice of comparison, and effectiveness of arrangement at which Mr.
Ajor, having less knowledge of the effectiveness of firearms than I, and therefore greater confidence in them, entreated me to shoot the beast; but I knew that the chance that I could stop it with a single shot was most remote, while that I should but infuriate it was real and present; and so I waited for what seemed an eternity, watching those devilish points of fire glaring balefully at us, and listening to the ever-increasing volume of those seismic growls which seemed to rumble upward from the bowels of the earth, shaking the very cliffs beneath which we cowered, until at last I saw that the brute was again approaching the aperture.
As I told you before, we have both, in our way, been successful, but we have reached the absolute limit of our effectiveness.
In a drama, and to some extent in other forms of narrative, dramatic power culminates in the ability to bring out the great crises with supreme effectiveness.
As you may imagine I was not very anxious to resume the discussion on the justice, expediency, effectiveness or what not, of Fyne's journey to London.
Letheringham's Cabinet, of course, would be a moderate Liberal one, a paragon of milk and water in effectiveness.
He required a more perfect form of ease; or it might have been that he was the victim of a philosophical unbelief in the effectiveness of every human effort.
Sales Force Effectiveness in Pharmaceuticals - Targeted Sales Models such as Enhanced Key Account Management (KAM) and Closed-Loop Marketing (CLM) Strategies Drives Sales Force Efficiency
There's no denying the sober intent of federal and state officials calling for accountability measures--questioning the effectiveness Of colleges and universities and inventing methods to rate (even rank) them.