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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.


thoroughly; completely; fundamentally: to alter radically.


(ˈræd ɪk li)

1. with regard to origin or root.
2. in a complete or basic manner; thoroughly; fundamentally.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.radically - in a radical manner; "she took a radically different approach"
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


[ˈrædɪkəli] adv (= fundamentally) [change, alter] → radicalement; [different, better] → radicalement


adv change, differ, improveradikal, grundlegend; there’s something radically wrong with thishier stimmt etwas ganz und gar nicht


[ˈrædɪklɪ] advradicalmente


(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
References in classic literature ?
A soldier -- New England's most distinguished soldier -- he stood firmly on the pedestal of his gallant services; and, himself secure in the wise liberality of the successive administrations through which he had held office, he had been the safety of his subordinates in many an hour of danger and heart-quake General Miller was radically conservative; a man over whose kindly nature habit had no slight influence; attaching himself strongly to familiar faces, and with difficulty moved to change, even when change might have brought unquestionable improvement.
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.
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 was on the moral side, and in my own person, that I learned to recognise the thorough and primitive duality of man; I saw that, of the two natures that contended in the field of my consciousness, even if I could rightly be said to be either, it was only because I was radically both; and from an early date, even before the course of my scientific discoveries had begun to suggest the most naked possibility of such a miracle, I had learned to dwell with pleasure, as a beloved daydream, on the thought of the separation of these elements.
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.
To Beatrice,--so radically had her earthly part been wrought upon by Rappaccini's skill,--as poison had been life, so the powerful antidote was death; and thus the poor victim of man's ingenuity and of thwarted nature, and of the fatality that attends all such efforts of perverted wisdom, perished there, at the feet of her father and Giovanni.
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.
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.
Such was my sunset mood; it lasted a few minutes, and then, without radically changing, it became more objective.
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.
The Swift One was radically different from any of the females of the horde, and I had a liking for her from the first.