free radical


nounChemistry, Biochemistry.
  1. an atom or molecule that bears an unpaired electron and is extremely reactive, capable of engaging in rapid chain reactions that destabilize other molecules and generate many more free radicals: in the body, deactivated by antioxidants, uric acid, and certain enzyme activities.

Origin of free radical

1
First recorded in 1895–1900

Words Nearby free radical

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British Dictionary definitions for free radical

free radical

noun
  1. an atom or group of atoms containing at least one unpaired electron and existing for a brief period of time before reacting to produce a stable molecule: Sometimes shortened to: radical Compare group (def. 10)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for free radical

free radical

  1. An atom or group of atoms that has at least one unpaired electron and is therefore unstable and highly reactive. In animal tissues, free radicals can damage cells and are believed to accelerate the progression of cancer, cardiovascular disease, and age-related diseases.

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