Affect v. to influence.
Effect n. result or outcome.
Words in the Wild: The dreadful effects of her childish pranks will almost certainly affect her brother’s decision about loaning her the money.
In common use, affect is almost always a verb with the definition shown above, and effect is most often a noun as defined above.
There are, however, less common meanings of both words. These meanings are likely to blame for the confusion that besets writers trying to figure out which of these words they’re looking for. Here are two of these meanings that you’ll happen across from time to time:
Affect n. mood or feeling. (This term is a technical one particular to the study of psychology and sociology.)
Words in the Wild: The subject’s ability to control her affect after a traumatic event is directly related to her ability to effect positive changes in her life years after the event takes place.
Both affect and effect have even more meanings than those listed here. In the interests of brevity and because those meanings crop up only infrequently, I’ve excluded them from this entry. But if you’re dying to learn more about effect and affect, I encourage you to check out this excellent resource by Malcolm D. Gibson, a onetime newspaper editor who is now a professor of journalism at the University of Kansas.
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