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
The system contains unverified reports of side effects, including from patients, doctors and pharmacists.
—
Annika Kim Constantino, CNBC, 12 Sep. 2025
Federal health officials have said side effects are extremely rare.
—Lawrence Mower, Miami Herald, 12 Sep. 2025
Amen emphasized that some people may feel more tired at first, but this side effect usually abates.
—Angelica Stabile, FOXNews.com, 12 Sep. 2025
Temporary discomfort during the exam is the main side effect.
—Mark Gurarie, Health, 12 Sep. 2025
See All Example Sentences for side effect
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Annika Kim Constantino, CNBC, 12 Sep. 2025
Federal health officials have said side effects are extremely rare.
—Lawrence Mower, Miami Herald, 12 Sep. 2025
Amen emphasized that some people may feel more tired at first, but this side effect usually abates.
—Angelica Stabile, FOXNews.com, 12 Sep. 2025
Temporary discomfort during the exam is the main side effect.
—Mark Gurarie, Health, 12 Sep. 2025
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 Sep. 2025.
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