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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.
(Chemistry) 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 group10
a molecular fragment that bears one or more unpaired electrons and is therefore highly reactive.
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|Noun||1.||free radical - an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule; "in the body free radicals are high-energy particles that ricochet wildly and damage cells"|
atom - (physics and chemistry) the smallest component of an element having the chemical properties of the element