side effect

noun

Definition of side effect

: 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.
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Recent Examples on the Web

But the list of possible side effects is long—and scary. Tatiana Boncompagni, Harper's BAZAAR, "Inside Hollywood's Dangerous Anti-Aging Secret," 21 May 2019 With weekly dialysis treatments came a multitude of side effects: weight loss, sciatica, fluid retention and vision damage. Amanda Mitchell, Marie Claire, "Sarah Hyland Talks to 'Self' About Her Second Kidney Transplant and Suicidal Thoughts," 10 Dec. 2018 But chances are, that even with more accurate data the simulations will tell scientists what many of them already suspect: altering the earth’s climate is risky and carries a lot of side effects. Avery Thompson, Popular Mechanics, "Harvard Scientists Are Really Launching a Sun-Blocking Geoengineering Experiment," 5 Dec. 2018 One of the side effects is particularly odiferous gassy emissions; the underwear was a way to make her quality of life just a little bit better. Jennifer Ouellette, Ars Technica, "Here are your 2018 Ig Nobel Prize winners," 13 Sep. 2018 Jordan, who grows her own pot, testified that smoking marijuana treats a variety of life-threatening side effects of the disease and that other forms of ingestion don’t have the same positive impact. Dara Kam, OrlandoSentinel.com, "Smokable medical pot case stays on hold," 3 July 2018 Jordan, who grows her own pot, testified that smoking marijuana treats a variety of life-threatening side effects of the disease and that other forms of ingestion don’t have the same positive impact. Dara Kam, Sun-Sentinel.com, "Smoking medical marijuana not allowed while legal fight continues," 3 July 2018 Without proper Lyme disease treatment, the disease can linger on for years with a wide range of side effects from sore joints and memory problems to panic attacks and acid reflux, according to the International Lyme and Associated Diseases Society. Leah Zerbe, Good Housekeeping, "5 Effective Ways to Keep Ticks Out of Your Yard," 26 May 2018 But there's a negative side effect that comes from viewers who use the open call for feedback as an invitation to share their darkest thoughts, and the problem is growing. De Elizabeth, Glamour, "For The Bachelor Contestants, Is Finding Love and Spon-Con Deals Worth the Trolls?," 9 May 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'side effect.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of side effect

1814, in the meaning defined above

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Statistics for side effect

Last Updated

6 Jun 2019

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Time Traveler for side effect

The first known use of side effect was in 1814

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More Definitions for side effect

side effect

noun

English Language Learners Definition of side effect

: an often harmful and unwanted effect of a drug or chemical that occurs along with the desired effect
: a result of an action that is not expected or intended

side effect

noun

Medical Definition of side effect

: a secondary and usually adverse effect (as of a drug) toxic side effects a side effect of drowsiness caused by antihistamines

called also side reaction

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More from Merriam-Webster on side effect

Rhyming Dictionary: Words that rhyme with side effect

Spanish Central: Translation of side effect

Nglish: Translation of side effect for Spanish Speakers

Britannica English: Translation of side effect for Arabic Speakers

Britannica.com: Encyclopedia article about side effect

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