side effect


Definition of side effect

: a secondary and usually adverse effect (as of a drug) toxic side effects

called also side reaction

Examples of side effect in a Sentence

Nausea and diarrhea are the side effects of the drug. the harmful side effects of using chemicals to kill insects The merger created positive side effects for both companies.
Recent Examples on the Web There could be a positive SEO side effect of your efforts. Erica Gunn, Forbes, 18 July 2022 An increasing violent crime rate is not an inevitable side effect of a surging population, Drawve said. Stacy Ryburn, Arkansas Online, 17 July 2022 There should be far less slack and windup in the power delivery, but an increase in cabin vibration is almost certain to be a side effect. Dan Edmunds, Car and Driver, 19 May 2022 The conscious mental image, in other words, is just a side effect. Alison Gopnik, WSJ, 12 May 2022 Heart inflammation has been an extremely rare side effect of the mRNA vaccines. Brenda Goodman, CNN, 28 Apr. 2022 Inflation was a side effect of an economy running hot after the economically devastating first chapters of the pandemic, when Biden achieved the kind of growth that Presidents Barack Obama and Trump could not deliver. Calvin Woodward And Zeke Miller,, 27 Feb. 2022 Incontinence can also be associated with untreated prostate cancer or be a side effect of treatments for prostate cancer. Jessica Migala,, 22 Feb. 2022 This side effect is rare and most often occurs in adolescent males and young men, who are at elevated risk for the condition generally. Matthew Herper, STAT, 18 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'side effect.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of side effect

1814, in the meaning defined above

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Time Traveler for side effect

Time Traveler

The first known use of side effect was in 1814

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Dictionary Entries Near side effect

side drum

side effect

side-end lines

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Statistics for side effect

Last Updated

5 Aug 2022

Cite this Entry

“Side effect.” Dictionary, Merriam-Webster, Accessed 13 Aug. 2022.

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More Definitions for side effect

side effect


Medical Definition of side effect

: a secondary and usually adverse effect (as of a drug) toxic side effects a side effect of drowsiness caused by antihistamines

called also side reaction


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