side effect

noun
Updated on: 10 Dec 2017

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

  1. Nausea and diarrhea are the side effects of the drug.

  2. the harmful side effects of using chemicals to kill insects

  3. The merger created positive side effects for both companies.

Recent Examples of side effect from the Web

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.

First Known Use of side effect

1814


SIDE EFFECT Defined for English Language Learners

side effect

noun

Definition of side effect for English Language Learners

  • : 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


Medical Dictionary

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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