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Synonyms

effective

American  
[ih-fek-tiv, ee-fek‐] / ɪˈfɛk tɪv, iˈfɛk‐ /

adjective

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

    effective teaching methods; effective steps toward peace.

    Synonyms:
    competent, capable
    Antonyms:
    useless, futile
  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

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

  2. the effective total of a military force.

effective British  
/ 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

"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

noun

  1. a serviceman who is equipped and prepared for action

"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

Usage

What are other ways to say effective? The adjective effective describes things that are adequate to accomplish a purpose, or that produce the intended or expected result. But effective isn’t quite the same as effectual, efficacious, or efficient! Find out why on Thesaurus.com.

Related Words

operative. telling.

Other Word Forms

  • effectively adverb
  • effectiveness noun
  • effectivity noun
  • preeffective adjective
  • quasi-effective adjective
  • subeffective adjective
  • supereffective adjective
  • uneffective adjective

Etymology

Origin of effective

First recorded in 1350–1400; Middle English from Latin effectīvus “practical,” equivalent to effect(us), past participle of efficere ( effect ) + -īvus adjective suffix ( -ive )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It’s a primitive but effective tactic identified by psychologists as one used by manipulative or narcissistic people.

From MarketWatch

It’s a primitive but effective tactic identified by psychologists as one used by manipulative or narcissistic people.

From MarketWatch

Researchers have found that a pair of existing drugs is far more effective when used together than when either is taken alone.

From Science Daily

It was devastatingly effective; the so-called resistance was left reeling.

From Salon

“I have my doubts over how effective this can be.”

From The Wall Street Journal