radical

rad·i·cal  (rd-kl)

adj.

1. Arising from or going to a root or source; basic: proposed a radical solution to the problem.

2. Departing markedly from the usual or customary; extreme: radical opinions on education.

3. Favoring or effecting fundamental or revolutionary changes in current practices, conditions, or institutions: radical political views.

4. Linguistics Of or being a root: a radical form.

5. Botany Arising from the root or its crown: radical leaves.

6. Slang Excellent; wonderful.

n.

1. One who advocates fundamental or revolutionary changes in current practices, conditions, or institutions: radicals seeking to overthrow the social order.

2. Mathematics The root of a quantity as indicated by the radical sign.

3. Symbol R An atom or a group of atoms with at least one unpaired electron.

4. Linguistics See root¹.

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[Middle English, of a root, from Late Latin rdclis, having roots, from Latin rdx, rdc-, root; see wrd- in Indo-European roots.]

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radi·cal·ly adv.

radi·cal·ness n.

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radical

Adjective

1. favouring fundamental change in political or social conditions: a radical student movement

2. of the essential nature of a person or thing; fundamental: a radical fault

3. searching or thorough: a radical interpretation

4. Maths of or containing roots of numbers or quantities

Noun

1. a person who favours fundamental change in existing institutions or in political, social, or economic conditions

2. Maths a root of a number or quantity, such as ³∛5, ∛x

3. Chem an atom or group of atoms which acts as a unit during chemical reactions [Latin radix a root]

radicalism n
radically adv

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radical  (rd-kl)

1. A root, such as 2, especially as indicated by a radical sign ().

2. A group of atoms that behaves as a unit in chemical reactions and is often not stable except as part of a molecule. The hydroxyl, ethyl, and phenyl radicals are examples. Radicals are unchanged by chemical reactions.

Thesaurus

Noun	1.	radical - (chemistry) two or more atoms bound together as a single unit and forming part of a molecule chemical group, group chemical science, chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions building block, unit - a single undivided natural thing occurring in the composition of something else; "units of nucleic acids" acyl, acyl group - any group or radical of the form RCO- where R is an organic group; "an example of the acyl group is the acetyl group" alcohol group, alcohol radical - the chemical group -OH aldehyde group, aldehyde radical - the chemical group -CHO alkyl, alkyl group, alkyl radical - any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons allyl, allyl group, allyl radical - the univalent unsaturated organic radical C3H5; derived from propylene amino, amino group - the radical -NH2 amyl - a hydrocarbon radical that occurs in many organic compounds azido group, azido radical - the univalent group N3- derived from hydrazoic acid azo group, azo radical - the bivalent group -N=N- united to two hydrocarbon groups benzyl, benzyl group, benzyl radical - the univalent radical derived from toluene benzoyl group, benzoyl radical - the univalent radical derived from benzoic acid molecule - (physics and chemistry) the simplest structural unit of an element or compound arsenic group, cacodyl group, cacodyl radical, cacodyl - the univalent group derived from arsine carbonyl group - the bivalent radical CO carboxyl, carboxyl group - the univalent radical -COOH; present in and characteristic of organic acids chromophore - the chemical group that gives color to a molecule cyanide group, cyanide radical, cyano group, cyano radical - the monovalent group -CN in a chemical compound glyceryl - a trivalent radical derived from glycerol by removing the three hydroxyl radicals hydrazo group, hydrazo radical - the bivalent group -HNNH- derived from hydrazine hydroxyl, hydroxyl group, hydroxyl radical - the monovalent group -OH in such compounds as bases and some acids and alcohols ketone group - a group having the characteristic properties of ketones methylene, methylene group, methylene radical - the bivalent radical CH2 derived from methane propyl, propyl group, propyl radical - the monovalent organic group C3H7- obtained from propane butyl - a hydrocarbon radical (C4H9) nitro group - the group -NO3 nitrite - the radical -NO2 or any compound containing it (such as a salt or ester of nitrous acid) uranyl, uranyl group, uranyl radical - the bivalent radical UO2 which forms salts with acids vinyl, vinyl group, vinyl radical - a univalent chemical radical derived from ethylene
	2.	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" free radical atom - (physics and chemistry) the smallest component of an element having the chemical properties of the element
	3.	radical - a person who has radical ideas or opinions individual, mortal, person, somebody, someone, soul - a human being; "there was too much for one person to do" anarchist, syndicalist, nihilist - an advocate of anarchism Bolshevik, bolshie, bolshy, Marxist, red - emotionally charged terms used to refer to extreme radicals or revolutionaries extremist - a person who holds extreme views leveler, leveller - a radical who advocates the abolition of social distinctions revolutionary, revolutionist, subversive, subverter - a radical supporter of political or social revolution terrorist - a radical who employs terror as a political weapon; usually organizes with other terrorists in small cells; often uses religion as a cover for terrorist activities Trotskyist, Trotskyite, Trot - radicals who support Trotsky's theory that socialism must be established throughout the world by continuing revolution Wobbly - a member of the Industrial Workers of the World young Turk - a young radical who agitates for reform
	4.	radical - (mathematics) a quantity expressed as the root of another quantity quantity, measure, amount - how much there is or how many there are of something that you can quantify math, mathematics, maths - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement
	5.	radical - a character conveying the lexical meaning of a logogram grapheme, graphic symbol, character - a written symbol that is used to represent speech; "the Greek alphabet has 24 characters" ideogram, ideograph - a graphic character that indicates the meaning of a thing without indicating the sounds used to say it; "Chinese characters are ideograms"
	6.	radical - (linguistics) the form of a word after all affixes are removed; "thematic vowels are part of the stem" root word, stem, root, theme, base linguistics - the scientific study of language descriptor, form, signifier, word form - the phonological or orthographic sound or appearance of a word that can be used to describe or identify something; "the inflected forms of a word can be represented by a stem and a list of inflections to be attached"
Adj.	1.	radical - (used of opinions and actions) far beyond the norm; "extremist political views"; "radical opinions on education"; "an ultra conservative" extremist, ultra immoderate - beyond reasonable limits; "immoderate laughter"; "immoderate spending"
	2.	radical - markedly new or introducing radical change; "a revolutionary discovery"; "radical political views" revolutionary new - not of long duration; having just (or relatively recently) come into being or been made or acquired or discovered; "a new law"; "new cars"; "a new comet"; "a new friend"; "a new year"; "the New World"
	3.	radical - arising from or going to the root or source; "a radical flaw in the plan" basic - pertaining to or constituting a base or basis; "a basic fact"; "the basic ingredients"; "basic changes in public opinion occur because of changes in priorities"
	4.	radical - of or relating to or constituting a linguistic root; "a radical verb form" linguistics - the scientific study of language
	5.	radical - especially of leaves; located at the base of a plant or stem; especially arising directly from the root or rootstock or a root-like stem; "basal placentation"; "radical leaves" basal phytology, botany - the branch of biology that studies plants cauline - especially of leaves; growing on a stem especially on the upper part of a stem; "cauline leaves"

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radical

adjective 1. extreme, complete, entire, sweeping, violent, severe, excessive, thorough, drastic

adjective 2. revolutionary, extremist, fanatical

adjective 3. fundamental, natural, basic, essential, native, constitutional, organic, profound, innate, deep-seated, thoroughgoing << OPPOSITE superficial

noun 4. extremist, revolutionary, militant, fanatic << OPPOSITE conservative

Translations

radical [ˈrædɪkl] adj → radical

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radical [ˈrædɪkl] adj → radical(e)

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radical [ˈrædɪkl] adj → radikal

n (person) → Radikale(r) f(m)

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radical [ˈrædɪkl] adj → radicale