radical


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radical

 [rad´ĭ-kal]
1. thorough or sweeping; directed to the cause or root 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.
color radical chromophore.
free radical a radical that carries an unpaired electron; such radicals are extremely reactive, with a very short half-life.
oxygen radical a toxic metabolite of oxygen, such as superoxide or singlet oxygen, capable of damaging microorganisms and normal tissues.

rad·i·cal

(rad'i-kăl), Do not confuse this word with radicle.
1. In chemistry, a group of elements or atoms usually passing intact from one compound to another, but usually incapable of prolonged existence in a free state (for example, methyl, CH3); in chemical formulas, a radical is often distinguished by being enclosed in parentheses or brackets.
2. Thorough or extensive; relating or directed to the extirpation of the root or cause of a morbid process; for example, a radical operation.
3. Denoting treatment by extreme, drastic, or innovative, as opposed to conservative, measures.
4. Synonym(s): free radical
5. A functional group in a molecule or molecular entity.
[L. radix (radic-), root]

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.

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

radical

(răd′ĭ-kəl)
adj.
1. Departing markedly from the usual or customary; extreme or drastic: a radical change in diet.
2. Medicine Relating to or being surgery that is extreme or drastic in an effort to eradicate all existing or potential disease: radical hysterectomy.
3. Botany
a. Of, relating to, or arising from a root: radical hairs.
b. Arising from the base of a stem or from a below-ground stem or rhizome: radical leaves.

rad′i·cal·ly adv.
rad′i·cal·ness n.

radical

[rad′ikəl]
Etymology: L, radix, root
1 n, an atom or group of atoms that contains an unpaired electron. A radical does not exist freely in nature except for O2, NO, and NO2.
2 adj, pertaining to drastic therapy, such as the surgical removal of an organ, limb, or other part of the body.

rad·i·cal

(rad'i-kăl)
1. chemistry A group of elements or atoms usually passing intact from one compound to another, but usually incapable of prolonged existence in a free state (e.g., methyl, CH3); in chemical formulas, a radical is often distinguished by being enclosed in parentheses or brackets.
2. Directed to the extirpation of the root or cause of a morbid process, e.g., a radical operation.
3. Denoting treatment by extreme, drastic, or innovative, as opposed to conservative, measures.
4. Synonym(s): free radical.
[L. radix (radic-), root]

radical

(of plants) arising from the root or crown.

rad·i·cal

(rad'i-kăl)
1. In chemistry, a group of elements or atoms usually passing intact from one compound to another, but usually incapable of prolonged existence in a free state (e.g., methyl, CH3).
2. Thorough or extensive; relating or directed to the extirpation of the root or cause of a morbid process.
3. Denoting treatment by extreme, drastic, or innovative, as opposed to conservative, measures.
[L. radix (radic-), root]

radical,

n 1. a group of atoms that acts together and forms a component of a compound. The group tends to remain bound together when a chemical reaction removes it from one compound and attaches it to another compound. A radical does not exist freely in nature.
adj 2. a drastic measure to cure or prevent the spread of a serious disease, such as the surgical removal of an organ, limb, or other body part.

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.

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.
References in periodicals archive ?
That said, any academic designing a course in politics and hoping to inject some radical thought into the mix would do well to consider adopting some of these entries as readings, especially since many of them lead invitingly from condensed, digestible coverage of the idea at hand towards more in-depth referencing of external literature.
Free radical scavengers actively search free radicals and bind them before they attach themselves to molecules and cause cross-linking.
Dealing first with what he considered Supreme Court encroachment on the Radical agenda, Stevens hammered home the First Reconstruction Act--passed on March 2, 1867--which grouped the former Confederate states into five military districts.
The latest book by former Advocate reporter Bruce Bawer, While Europe Slept: How Radical Islam Is Destroying the West From Within, includes personal accounts of intimidation by radical Islamists in his adopted home of Norway and profiles how appeasement of religious extremism is a huge risk for the West.
Its Dragon Slayer bike won the Super Radical class at the 2005 Rat's Hole Show in Daytona Beach, Fla.
23) Briggs remained active in radical black politics until his death from a heart attack in 1966.
But other developments have occurred in relation to the Radical Change theory since that 1997 article (Fisher, Erdelez, & McKenzie, 2005).
This research was carried out as part of a project to develop a high-power density organic radical battery for data-backup supported by the New Energy and Industrial Technology Development Organization ("NEDO").
Family Circle: The Boudins and the Aristocracy of the Left, a biography of Kathy Boudin and her comrades, is a cautionary tale that reminds us how lucky we were to escape the demented ambitions of the radical youth movements of that tumultuous era.
In effect, aminoglycosides are binding iron or copper molecules into active complexes and forming radical oxygen species that cause ototoxicity.
Influential legal bodies in both the United States and Canada have presented radical programs of marital reform.