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
As wellness, aesthetics and hospitality continue to converge, the glow-up is no longer a side effect of travel.
—
Amy Francombe, Vogue, 19 Dec. 2025
The whole mechanism route, the way testosterone works, and its side effects, are completely different.
—Stephanie Brown, Verywell Health, 19 Dec. 2025
Here are some of the benefits and side effects of your daily dose of java.
—Allison Forsyth, Health, 18 Dec. 2025
The most common side effects were gastrointestinal related and generally mild to moderate in severity.
—Annika Kim Constantino, CNBC, 18 Dec. 2025
See All Example Sentences for side effect
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Amy Francombe, Vogue, 19 Dec. 2025
The whole mechanism route, the way testosterone works, and its side effects, are completely different.
—Stephanie Brown, Verywell Health, 19 Dec. 2025
Here are some of the benefits and side effects of your daily dose of java.
—Allison Forsyth, Health, 18 Dec. 2025
The most common side effects were gastrointestinal related and generally mild to moderate in severity.
—Annika Kim Constantino, CNBC, 18 Dec. 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 24 Dec. 2025.
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