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
Still, side effects such as nausea, vomiting and constipation were reported in more than 70% of those who took the higher dose of Wegovy, compared to more than 60% taking the lower dose and about 43% taking a dummy medication, the study showed.
—
ABC News, 19 Mar. 2026
The most common side effects included headache, nausea, cough, fungal infection, and fatigue.
—Emily Kay Votruba, EverydayHealth.com, 19 Mar. 2026
Retatrutide has shown similar side effects, as well as a prickling sensation known as dysesthesia.
—Meg Tirrell, CNN Money, 19 Mar. 2026
The most common side effects among the trial group were nausea, diarrhea and vomiting.
—Jackie Flynn Mogensen, Scientific American, 19 Mar. 2026
See All Example Sentences for side effect
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ABC News, 19 Mar. 2026
The most common side effects included headache, nausea, cough, fungal infection, and fatigue.
—Emily Kay Votruba, EverydayHealth.com, 19 Mar. 2026
Retatrutide has shown similar side effects, as well as a prickling sensation known as dysesthesia.
—Meg Tirrell, CNN Money, 19 Mar. 2026
The most common side effects among the trial group were nausea, diarrhea and vomiting.
—Jackie Flynn Mogensen, Scientific American, 19 Mar. 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 28 Mar. 2026.
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