effective

[ih-fek-tiv] /ɪˈfɛk tɪv/

adjective

adequate to accomplish a purpose; producing the intended or expected result:

effective teaching methods; effective steps toward peace.

actually in operation or in force; functioning:

The law becomes effective at midnight.

producing a deep or vivid impression; striking:

an effective photograph.

prepared and available for service, especially military service.

noun

a member of the armed forces fit for duty or active service.

the effective total of a military force.

Origin

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.

Examples from the web 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

productive of or capable of producing a result

in effect; operative: effective from midnight

producing a striking impression; impressive: an effective entrance

(prenominal) actual rather than theoretical; real: the effective income after deductions

(of a military force, etc) equipped and prepared for action

(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

a serviceman who is equipped and prepared for action

Derived Forms

effectively, adverb
effectiveness, noun

Word Origin and History for 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.