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
Early results suggest the approach helps the heart repair itself while avoiding the systemic side effects that plagued earlier drug delivery methods.
—
Aamir Khollam, Interesting Engineering, 14 Nov. 2025
Use of either kind of these vapes can come with side effects, including drowsiness or dry mouths.
—Surina Venkat, The Hill, 14 Nov. 2025
Still, side effects remain a key reason why some people decide to stop taking them.
—Asuka Koda, CNN Money, 14 Nov. 2025
Some people may have negative digestive side effects, though.
—Joy Emeh, Health, 14 Nov. 2025
See All Example Sentences for side effect
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Aamir Khollam, Interesting Engineering, 14 Nov. 2025
Use of either kind of these vapes can come with side effects, including drowsiness or dry mouths.
—Surina Venkat, The Hill, 14 Nov. 2025
Still, side effects remain a key reason why some people decide to stop taking them.
—Asuka Koda, CNN Money, 14 Nov. 2025
Some people may have negative digestive side effects, though.
—Joy Emeh, Health, 14 Nov. 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 18 Nov. 2025.
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