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 ?
A slightly heavier version compared to the YouTek Graphene Radical Midplus version, the HEAD YouTek Graphene Radical Pro tennis racquet offers a more control-oriented feel, and is recommended for 4.
The first certification training for Radical Living Coaches and Radical Forgiveness Therapy Practitioners will occur in August.
Skin sagging and wrinkles are directly proportional to the free radical damage.
Ochs does assert that "post-liberal" Jews would not "expect the radical reformers [like Yoder] to bear the same responsibilities for landedness that Jews bear, just as they would not expect most Jews to bear the same responsibility for pacifism that the radical reformers bear.
The Radical Republicans were animated by their belief in big government--even Marxism--and they supported whatever degree of rancor or even further bloodshed necessary to centralize power in Washington and impose their ideology on North and South alike.
Is aristocracy a system of government, as it was for Aristotle, or a word synonymous with 'the landed interest', or is it merely a term of radical abuse?
Groups like the Islamic Thinkers are not nearly as prevalent in the United States as they are in the European Union, where many Muslim residents subscribe to a much more radical interpretation of Islam.
Radical Simplicity had its origins at the 2005 Grand National Roadster Show, where Paula Stafford's tangerine pearl bike named Teaser was runner-up.
For them, a more radical approach was necessary to bring about reform.
From Iran's standpoint, the less favorable outcome has always been one in which al Qaeda became the radical Muslim world's sole challenger to the West.
The Evolution and Application of Radical Change Theory
Tokyo, Japan, Aug 5, 2005 - (JCN Newswire) - NEC Corporation today announced that it is developing a high-power organic radical battery ("ORB") used to protect IT equipment such as desktop PCs from losing data during power supply interruption.