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
Continuing with immunotherapy, Shahi remains determined to maintain her health since managing the numerous side effects from her treatments and medications comes with its challenges.
—
Tereza Shkurtaj, PEOPLE, 25 Oct. 2025
Post- and peri-menopausal women, who have long been left to deal with the side effects of the naturally declining levels of testosterone that accompany aging, are turning to low doses of testosterone as a possible cure-all.
—Quispe López, Them., 24 Oct. 2025
The most common side effects in women taking the drug were drowsiness, fatigue and headaches.
—Jacqueline Howard, CNN Money, 24 Oct. 2025
The doctors found blood clots in my lungs, a rare side effect from my surgery.
—Megan Sauer, CNBC, 24 Oct. 2025
See All Example Sentences for side effect
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Tereza Shkurtaj, PEOPLE, 25 Oct. 2025
Post- and peri-menopausal women, who have long been left to deal with the side effects of the naturally declining levels of testosterone that accompany aging, are turning to low doses of testosterone as a possible cure-all.
—Quispe López, Them., 24 Oct. 2025
The most common side effects in women taking the drug were drowsiness, fatigue and headaches.
—Jacqueline Howard, CNN Money, 24 Oct. 2025
The doctors found blood clots in my lungs, a rare side effect from my surgery.
—Megan Sauer, CNBC, 24 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 28 Oct. 2025.
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