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

(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.

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]
References in periodicals archive ?
'With this bold move, Radical is reinforcing its ability to get stuff done in some of the most complex and most regulated environments.
What radical means is different from generation to generation, from baby boomers to millennials.
Kelly Fritsch, Clare O'Connor and AK Thompson (eds), Keywords for Radicals: The Contested Vocabulary of Late-Capitalist Struggle Edinburgh: AK Press, 2016; 572pp; ISBN 9781849352420
The first important factor is the examination of the interaction nature of the [C.sup.1]-centered and [C.sup.2]-centered radicals respectively with fullerene as a function of the rotations [eta] with rotate step 10", see Fig.
Q.: Do free radicals contribute to how quickly a cell ages?
(1) For the cosmetic chemist, free radicals play a key role in aging.
The Radical sanitising system provides the peace of mind that our sanitising system is the very best available."
Standing in their way was Andrew Johnson, who steadfastly opposed the Radical Republicans' attempt to employ extraconstitutional federal powers to enslave the South--even if his principled opposition meant the loss of the presidency.
For Rossi, the rise of globalization looks to the heart of the dilemma of radical evil, exacerbating the "unsociable sociability" that is the hallmark of radical evil.
Does radical religion sway the Republican Party now more than it has in the past?
Q: Do you think radical Islam poses a threat to the well-being of gays and lesbians in the United States?
Key statement: A functional polymer having at least one substituent capable of forming a stable free radical is formed by polymerizing a diene monomer, such as butadiene, to form a first polymer block of the functional polymer.