[ ih-fekt ]
/ ɪˈfɛkt /
Save This Word!
See synonyms for: effect / effected / effecting / effects on Thesaurus.com


verb (used with object)

to produce as an effect; bring about; make happen; accomplish: The new machines finally effected the transition to computerized accounting last spring.


WATCH NOW: How To Use "Affect" vs. "Effect"

Effect and affect: can you keep these two words straight? We can't either which is why we are giving you some examples to learn the difference between the two!




Apostrophes can be tricky; prove you know the difference between it’s and its in this crafty quiz!
Question 1 of 12
On the farm, the feed for chicks is significantly different from the roosters’; ______ not even comparable.

Idioms for effect

    in effect,
    1. for practical purposes; virtually: His silence was in effect a confirmation of the rumor.
    2. essentially; basically.
    3. operating or functioning; in force: The plan is now in effect.
    take effect,
    1. to go into operation; begin to function.
    2. to produce a result: The prescribed medicine failed to take effect.

Origin of effect

First recorded in 1350–1400; Middle English, from Latin effectus “the carrying out (of a task, etc.),” hence, “accomplishment, outcome,” equivalent to effec- (variant stem of efficere “to make, carry out”; ef- combining form meaning “out, out from, beyond” + -ficere combining form of the verb facere “do, make”) + -tus suffix of verbal action; cf. ef-, do1
1. Effect, consequence(s), result refer to something produced by an action or a cause. An effect is that which is produced, usually more or less immediately and directly: The effect of morphine is to produce sleep. A consequence, something that follows naturally or logically, as in a train of events or sequence of time, is less intimately connected with its cause than is an effect: Punishment is the consequence of disobedience. A result may be near or remote, and often is the sum of effects or consequences as making an end or final outcome: The English language is the result of the fusion of many different elements.
See affect1.
affect, effect (see confusables note at affect1)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021


What's the difference between effect and affect?

Effect is most commonly used as a noun meaning a result or consequence. Affect is most commonly used as a verb meaning to act on or produce a change in someone or something.

Remembering the difference between the words can be especially hard because these senses of the words have just about the same pronunciation. Complicating things further is the fact that effect can also be used as a verb (meaning to make happen, as in We can only effect change by taking action) and affect can also be used as a noun (referring to a state of emotion, as in He had a sad affect). However, these senses of the words are much less commonly used.

You can remember that affect is most commonly used as a verb because it begins with a, for action.

You can also remember how effect and affect are most commonly used by using the acronym RAVEN:

R = Remember
A = Affect is
V = Verb
E = Effect is a
N = Noun

Here’s an example of effect and affect used correctly in the same sentence.

Example: It’s unclear what immediate effects the new law will have or how it will affect future generations.

Want to learn more? Read the full breakdown of the difference between effect and affect.

Quiz yourself on effect vs. affect!

Should effect or affect be used in the following sentence?

The campaign is hoping that the ads have a big _____ on voter turnout.

British Dictionary definitions for effect

/ (ɪˈfɛkt) /



(tr) to cause to occur; bring about; accomplish
See also effects
effecter, nouneffectible, adjective
C14: from Latin effectus a performing, tendency, from efficere to accomplish, from facere to do
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

Medical definitions for effect

[ ĭ-fĕkt ]



ef•fecti•ble adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Idioms and Phrases with effect


see in effect; into effect; take effect; to that effect.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
Hate Typos? Get Grammar Coach