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
The study said adverse side effects and cost were the most common reasons patients stopped the drugs that were documented in clinical notes.
—
Annika Kim Constantino,ashley Capoot, CNBC, 4 Feb. 2025
People who had moderate or severe digestive side effects were more likely to stop the medications.
—Ken Alltucker, USA TODAY, 2 Feb. 2025
Most lash enhancers don’t have any side effects beyond possible irritation for those with sensitive skin.
—Bestreviews, Chicago Tribune, 31 Jan. 2025
This advice also applies to fiber supplements, which can trigger side effects like nausea or bowel obstructions.16
People with a digestive disorder should check with a healthcare provider before starting a high-fiber diet to avoid potentially worsening symptoms.
—Cristina Mutchler, Health, 30 Jan. 2025
See all Example Sentences for side effect 
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Annika Kim Constantino,ashley Capoot, CNBC, 4 Feb. 2025
People who had moderate or severe digestive side effects were more likely to stop the medications.
—Ken Alltucker, USA TODAY, 2 Feb. 2025
Most lash enhancers don’t have any side effects beyond possible irritation for those with sensitive skin.
—Bestreviews, Chicago Tribune, 31 Jan. 2025
This advice also applies to fiber supplements, which can trigger side effects like nausea or bowel obstructions.16
People with a digestive disorder should check with a healthcare provider before starting a high-fiber diet to avoid potentially worsening symptoms.
—Cristina Mutchler, Health, 30 Jan. 2025
See all Example Sentences for side effect
Dictionary Entries Near side effect
Cite this Entry
“Side effect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/side%20effect. Accessed 11 Feb. 2025.
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