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
Many people experience side effects such as nausea, heartburn, diarrhea, and abdominal pain after surgery.
—
Carrie Madormo, Health, 18 Oct. 2025
Concerns about finasteride's psychiatric side effects aren't new.
—Pranjal Malewar, New Atlas, 18 Oct. 2025
For consumers and companies, the positive climate outcomes are welcome side effects.
—Justin Worland, Time, 17 Oct. 2025
In men, it’s been associated with side effects like erectile dysfunction and decreased libido.
—Marci Robin, Allure, 17 Oct. 2025
See All Example Sentences for side effect
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Carrie Madormo, Health, 18 Oct. 2025
Concerns about finasteride's psychiatric side effects aren't new.
—Pranjal Malewar, New Atlas, 18 Oct. 2025
For consumers and companies, the positive climate outcomes are welcome side effects.
—Justin Worland, Time, 17 Oct. 2025
In men, it’s been associated with side effects like erectile dysfunction and decreased libido.
—Marci Robin, Allure, 17 Oct. 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 Oct. 2025.
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