If your email outlining a plan to reduce office paper waste resulted in a 20 percent reduction in paper use, that means your plan was effective: it did what you wanted it to do.

The adjective effective has many shades of meaning, but you'll usually see it describing something that's able to produce a desired goal. Effective traces back to the Latin word effectivus, from efficere, meaning “work out, accomplish,” and that meaning still holds true. Something effective gets the job done. As President, hopefully your policies are effective. We also use effective for something real and in effect, like the effective price of gas, or your effective grounding.

Definitions of effective
  1. adjective
    producing or capable of producing an intended result or having a striking effect
    “"an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation"-LewisMumford”
    effective teaching methods”
    effective steps toward peace”
    “made an effective entrance”
    synonyms: effectual, efficacious
    hard-hitting, trenchant
    characterized by or full of force and vigor
    markedly effective as if by emotional pressure
    impressive, telling
    producing a strong effect
    crude but effective for the purpose at hand
    marked by qualities giving the power to produce an intended effect
    being effective without wasting time or effort or expense
    potent, stiff, strong
    having a strong physiological or chemical effect
    having great power or force or potency or effect
    useful, utile
    being of use or service
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    ineffective, ineffectual, uneffective
    not producing an intended effect
    not in action or at work
    lacking necessary force for effectiveness
    not producing desired results
    lacking the power to produce a desired effect
    not producing desired results; wasteful
    lacking power
    having no beneficial use or incapable of functioning usefully
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  2. adjective
    works well as a means or remedy
    “an effective reprimand”
    “a lotion that is effective in cases of prickly heat”
    marked by qualities giving the power to produce an intended effect
  3. adjective
    able to accomplish a purpose; functioning effectively
    “"people who will do nothing unless they get something out of it for themselves are often highly effective persons..."-G.B.Shaw”
    effective personnel”
    synonyms: efficient
    properly or sufficiently qualified or capable or efficient
  4. adjective
    exerting force or influence
    “the law is effective immediately”
    synonyms: good, in effect, in force
    being in force or having or exerting force
  5. adjective
    existing in fact; not theoretical; real
    “a decline in the effective demand”
    “confused increased equipment and expenditure with the quantity of effective work done”
    actual, existent
    presently existing in fact and not merely potential or possible
  6. adjective
    ready for service
    “the fort was held by about 100 effective soldiers”
    (military) of or intended for or involved in military operations
Word Family

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