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
Gastrointestinal Effects By far, the most common side effects patients will have will be gastrointestinal side effects like nausea, vomiting, diarrhea and constipation.
—
Omer Awan, Forbes.com, 17 June 2025
Taking a magnesium supplement by mouth can cause side effects like stomach pain, nausea, and diarrhea.
—Health, 16 June 2025
What This Means For You Magnesium is essential for your health, but taking too much in supplement form can lead to serious side effects.
—Abby Norman, Verywell Health, 13 June 2025
The surgery that saved her life last year did leave the girl with some lasting side effects.
—Nicole Acevedo, NBC news, 12 June 2025
See All Example Sentences for side effect
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Omer Awan, Forbes.com, 17 June 2025
Taking a magnesium supplement by mouth can cause side effects like stomach pain, nausea, and diarrhea.
—Health, 16 June 2025
What This Means For You Magnesium is essential for your health, but taking too much in supplement form can lead to serious side effects.
—Abby Norman, Verywell Health, 13 June 2025
The surgery that saved her life last year did leave the girl with some lasting side effects.
—Nicole Acevedo, NBC news, 12 June 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 20 Jun. 2025.
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