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
Physical side effects can include raised blood pressure and nausea.
—
Natalia V. Osipova, CNN Money, 28 Mar. 2026
What are the side effects and weaknesses of mRNA vaccines?
—Meghan Bartels, Scientific American, 27 Mar. 2026
GLP-1s also have side effects such as nausea that might impact someone’s workout, Gary notes.
—Caitlin Carlson, SELF, 27 Mar. 2026
The effectiveness, safety, and side effects are similar to daily shots.
—Emily Kay Votruba, EverydayHealth.com, 27 Mar. 2026
See All Example Sentences for side effect
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Natalia V. Osipova, CNN Money, 28 Mar. 2026
What are the side effects and weaknesses of mRNA vaccines?
—Meghan Bartels, Scientific American, 27 Mar. 2026
GLP-1s also have side effects such as nausea that might impact someone’s workout, Gary notes.
—Caitlin Carlson, SELF, 27 Mar. 2026
The effectiveness, safety, and side effects are similar to daily shots.
—Emily Kay Votruba, EverydayHealth.com, 27 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 29 Mar. 2026.
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