free radical

radical /rad·i·cal/ (rad´ĭ-k'l)

1. directed to the root or cause; designed to eliminate all possible extensions of a morbid process.

2. a group of atoms that enters and goes out of chemical combination without change.

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free radical  a radical that carries an unpaired electron; such radicals are extremely reactive, with a very short half-life.

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free radical

n.

1. An uncharged atom or group of atoms having at least one unpaired electron, which makes it highly reactive.

2. An organic compound having some unpaired valence electrons; a normal byproduct of oxidation reactions in metabolism.

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Free radical

An unstable molecule that causes oxidative damage by stealing electrons from surrounding molecules, thereby disrupting activity in the body's cells.

Mentioned in: Smoking

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free radical,

a species with at least one unpaired electron. Oxygen is a stable diradical, but most other free radicals are unstable and react readily with other molecules.

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free radical,

n a compound with an unpaired electron or proton. It is unstable and reacts readily with other molecules.

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radical

1. directed to the cause; going to the root or source of a morbid process.

2. a group of atoms that enters into and goes out of chemical combination without change and that forms one of the fundamental constituents of a molecule.

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free radical

a radical, extremely reactive, and having a very short half-life (10⁻⁵ s or less in an aqueous solution), which carries an unpaired electron.

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free radical

Physiology Any of a family of highly reactive molecules containing an unpaired electron in the outer orbital–eg, the excited variants of O₂; FRs cause random damage to structural proteins, enzymes, macromolecules, DNA, playing major roles in inflammation, hyperoxidation, post-ischemic tissue damage, infarction, possibly also CA and tissue damage in transplants. See Antioxidants, Free radical scavenger, Free radical theory Vox populi Freed radical A paroled political polemicist.