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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 or drastic: a radical change in diet.
3. Relating to or advocating fundamental or revolutionary changes in current practices, conditions, or institutions: radical politics; a radical political theorist.
4. Medicine Relating to or being surgery that is extreme or drastic in an effort to eradicate all existing or potential disease: radical hysterectomy.
5. Linguistics Of or being a root: a radical form.
6. 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.
7. Slang Excellent; wonderful.
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 one unpaired electron.
4. Linguistics See root1.
a. Any of the basic Chinese characters that are combined to form more complex characters.
b. Any of the traditional set of basic strokes or groups of strokes that make up Chinese characters and are used to classify and organize them in dictionaries.

[Middle English, of a root, from Late Latin rādīcālis, having roots, from Latin rādīx, rādīc-, root; see wrād- in Indo-European roots.]

rad′i·cal·ly adv.
rad′i·cal·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


thoroughly; completely; fundamentally: to alter radically.
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈræd ɪk li)

1. with regard to origin or root.
2. in a complete or basic manner; thoroughly; fundamentally.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.radically - in a radical manner; "she took a radically different approach"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
بِصورَةٍ مُتَطَرِّفَه
perin pohjinradikaalistitäysin
á róttækan hátt
kök dentemel den


[ˈrædɪkəlɪ] ADV [differ, change, improve, reduce, affect] → radicalmente, de forma radical; [different, changed, new] → radicalmente
to disagree with sb radicallyestar en total desacuerdo con algn
there's something radically wrong with his kneehay algo en su rodilla que no marcha bien en absoluto
his assessment of the situation had been radically wrongsu valoración de la situación había sido totalmente equivocada
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[ˈrædɪkəli] adv (= fundamentally) [change, alter] → radicalement; [different, better] → radicalement
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


adv change, differ, improveradikal, grundlegend; there’s something radically wrong with thishier stimmt etwas ganz und gar nicht
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ˈrædɪklɪ] advradicalmente
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(ˈrӕdikəl) adjective
1. relating to the basic nature of something. radical faults in the design.
2. thorough; complete. radical changes.
3. wanting or involving great or extreme political, social or economic changes.
a person who wants radical political changes.
ˈradically adverb
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
References in classic literature ?
The indiscreet zeal of the adversaries to the Constitution has betrayed them into an attack on this part of it also, without which it would have been evidently and radically defective.
It is not too much to say, that the deliberate employer of a cut-glass shade, is either radically deficient in taste, or blindly subservient to the caprices of fashion.
Such was my sunset mood; it lasted a few minutes, and then, without radically changing, it became more objective.
The Swift One was radically different from any of the females of the horde, and I had a liking for her from the first.
In short, he was taking an interest in the game, although a radically different interest from what he had taken with Skipper.
had once undertaken to erect a cabin in some remote part of it, but for some reason had abandoned the enterprise and constructed his present hermaphrodite habitation, half residence and half groggery, at the roadside, upon an extreme corner of his estate; as far away as possible, as if on purpose to show how radically he had changed his mind.
It is inconceivable that any sane man can radically disagree with one's most sane conclusions.
It must be by this time evident to all men of reflection, who can divest themselves of the prepossessions of preconceived opinions, that it is a system so radically vicious and unsound, as to admit not of amendment but by an entire change in its leading features and characters.
I did not, it is true, like my position in his house; but being freed from the annoyance of false professions and double-dealing I could endure it, especially as no heroic sentiment of hatred or jealousy of the director distracted my philosophical soul; he had not, I found, wounded me in a very tender point, the wound was so soon and so radically healed, leaving only a sense of contempt for the treacherous fashion in which it had been inflicted, and a lasting mistrust of the hand which I had detected attempting to stab in the dark.
That there was something radically wrong with the flier was evident from its lack of buoyancy, and the further fact that though Thurid had turned twice to the starting lever the boat still hung motionless in the air, except for a slight drifting with a low breeze from the north.
A freak of fate had thrown these three radically different types together.
His keen eyes detected at once that something was radically wrong, and when he had heard Mugambi's story his jaws clicked angrily together as he knitted his brows in thought.