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noun ef·fect \i-ˈfekt, e-, ē-, ə-\

Simple Definition of effect

  • : a change that results when something is done or happens : an event, condition, or state of affairs that is produced by a cause

  • : a particular feeling or mood created by something

  • : an image or a sound that is created in television, radio, or movies to imitate something real

Full Definition of effect

  1. 1 a :  purport, intent b :  basic meaning :  essence

  2. 2 :  something that inevitably follows an antecedent (as a cause or agent)

  3. 3 :  an outward sign :  appearance

  4. 4 :  accomplishment, fulfillment

  5. 5 :  power to bring about a result :  influence <the content itself of television … is therefore less important than its effectCurrent Biography>

  6. 6 plural :  movable property :  goods <personal effects>

  7. 7 a :  a distinctive impression <the color gives the effect of being warm> b :  the creation of a desired impression <her tears were purely for effect> c (1) :  something designed to produce a distinctive or desired impression —usually used in plural (2) plural :  special effects

  8. 8 :  the quality or state of being operative :  operation <the law goes into effect next week>

in effect
  1. :  in substance :  virtually <the … committee agreed to what was in effect a reduction in the hourly wage — Current Biography>

to the effect
  1. :  with the meaning <issued a statement to the effect that he would resign>

Examples of effect

  1. The nation's most solvent individuals—private-equity barons—have not been immune from the ill effects of the credit crunch. —Daniel Gross, Newsweek, 3 Mar. 2008

  2. In the Spanish conquest of the Incas, guns played only a minor role. … They did produce a big psychological effect on those occasions when they managed to fire. —Jared M. Diamond, Guns, Germs, and Steel, 1997

  3. Economic effects of such high speed change are also unpredictable and somewhat chilling … —Genevieve Stuttaford, Publisher's Weekly, 29 July 1996

  4. Unlike the venom of coral snakes, fer-de-lance venom has no direct effect on the nervous system but digests muscle, destroys blood cells and causes hemorrhaging and massive edema (swelling). —Robert K. Colwell, Natural History, April 1985

  5. He now needs more of the drug to achieve the same effect.

  6. The experience has had a bad effect on him.

  7. Computers have had a profound effect on our lives.

  8. The effects of the drug soon wore off.

  9. This treatment causes fewer ill effects.

  10. The change in policy had little effect on most people.

  11. He was able to stop taking the drug without ill effect.

  12. The total effect of the painting was one of gloom.

  13. The color gives the effect of being warm.

  14. He achieves amazing effects with wood.

Origin of effect

Middle English, from Anglo-French & Latin; Anglo-French, from Latin effectus, from efficere to bring about, from ex- + facere to make, do — more at do

First Known Use: 14th century



verb ef·fect \i-ˈfekt, e-, ē-, ə-\

Simple Definition of effect

  • : to cause (something) : to make (something) happen

  • : to cause (something) to produce the desired result

Full Definition of effect

  1. transitive verb
  2. 1 :  to cause to come into being

  3. 2 a :  to bring about often by surmounting obstacles :  accomplish <effect a settlement of a dispute> b :  to put into operation <the duty of the legislature to effect the will of the citizens>

Usage Discussion of effect

Effect and affect are often confused because of their similar spelling and pronunciation. The verb 2affect usually has to do with pretense <she affected a cheery disposition despite feeling down>. The more common 3affect denotes having an effect or influence <the weather affected everyone's mood>. The verb effect goes beyond mere influence; it refers to actual achievement of a final result <the new administration hopes to effect a peace settlement>. The uncommon noun affect, which has a meaning relating to psychology, is also sometimes mistakenly used for the very common effect. In ordinary use, the noun you will want is effect <waiting for the new law to take effect> <the weather had an effect on everyone's mood>.

Examples of effect

  1. When, at last, rescue is at hand, Jewitt has no hesitation in lying to his old friend and master, Maquinna, in order to effect his escape, although he does persuade the captain of the brig Lydia not to kill the chief. —Carolyn Kizer, New York Times Book Review, 21 Feb. 1988

  2. I had just written the Gossets that your address was Drujon Lane, so I would be obliged if you would drop them a card and tell them your release has been effected. —Flannery O'Connor, The Habit of Being, 1979

  3. As the whole progress of mathematics from its ancient simplicities to what we call its “higher” modern developments has been effected by assuming impossibilities and inconceivabilities, your line of argument does not seem to me conclusive. —Bernard Shaw, c. 4 Nov. 1932, in Collected Letters: 1926–1950, 1988

  4. Hitherto, while gathering up the discourse of Mr. Brocklehurst and Miss Temple, I had not, at the same time, neglected precautions to secure my personal safety; which I thought would be effected, if I could only elude observation. —Charlotte Brontë, Jane Eyre, 1847

  5. They are trying to effect a settlement of the dispute.

  6. The duty of the legislature is to effect the will of the people.

Origin of effect

(see 1effect)

First Known Use: 1533

Synonym Discussion of effect

perform, execute, discharge, accomplish, achieve, effect, fulfill mean to carry out or into effect. perform implies action that follows established patterns or procedures or fulfills agreed-upon requirements and often connotes special skill <performed gymnastics>. execute stresses the carrying out of what exists in plan or in intent <executed the hit-and-run>. discharge implies execution and completion of appointed duties or tasks <discharged his duties>. accomplish stresses the successful completion of a process rather than the means of carrying it out <accomplished everything they set out to do>. achieve adds to accomplish the implication of conquered difficulties <achieve greatness>. effect adds to achieve an emphasis on the inherent force in the agent capable of surmounting obstacles <effected sweeping reforms>. fulfill implies a complete realization of ends or possibilities <fulfilled their ambitions>.

EFFECT Defined for Kids



noun ef·fect \i-ˈfekt\

Definition of effect

  1. 1 :  an event, condition, or state of affairs that is produced by a cause :  influence <Computers have had an important effect on the way people work.>

  2. 2 :  the act of making a certain impression <The tears were only for effect.>

  3. 3 :  execution 2, operation <The law goes into effect today.>

  4. 4 effects plural :  personal property or possessions <household effects>

  5. 5 :  something created in film, television, or radio to imitate something real <sound effects>

in effect
  1. :  in actual fact <The suggestion was in effect an order.>



verb ef·fect

Definition of effect


  1. :  to make happen :  bring about <effect a change>

Medical Dictionary


noun ef·fect \i-ˈfekt\

Medical Definition of effect

  1. :  something that is produced by an agent or cause <obtained the same effect with a smaller dose>

Seen and Heard

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February 9, 2016

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