side effect
noun
: 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
But some say these medications didn’t work for them due to side effects or lack of progress.
—
Nicole Hernandez, USA Today, 11 May 2026
You are encouraged to report negative side effects of prescription drugs to the FDA.
—Cristina Velocci, Flow Space, 11 May 2026
Fainting is another side effect, Agarwal adds.
—Erica Sweeney, Time, 11 May 2026
And the side effects were generally mild.
—Sydney Lupkin, NPR, 10 May 2026
See All Example Sentences for side effect
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Nicole Hernandez, USA Today, 11 May 2026
You are encouraged to report negative side effects of prescription drugs to the FDA.
—Cristina Velocci, Flow Space, 11 May 2026
Fainting is another side effect, Agarwal adds.
—Erica Sweeney, Time, 11 May 2026
And the side effects were generally mild.
—Sydney Lupkin, NPR, 10 May 2026
See All Example Sentences for side effect
Cite this Entry
“Side effect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/side%20effect. Accessed 14 May. 2026.
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