Of or pertaining to the root; proceeding directly from the root.
Hence: Of or pertaining to the root or origin; reaching to the center, to the foundation, to the ultimate sources, to the principles, or the like; original; fundamental; thorough-going; unsparing; extreme; as, radical evils; radical reform; a radical party.
Belonging to, or proceeding from, the root of a plant; as, radical tubers or hairs.
Proceeding from a rootlike stem, or one which does not rise above the ground; as, the radical leaves of the dandelion and the sidesaddle flower.
Relating, or belonging, to the root, or ultimate source of derivation; as, a radical verbal form.
Of or pertaining to a radix or root; as, a radical quantity; a radical sign. See below.
A primitive word; a radix, root, or simple, underived, uncompounded word; an etymon.
A primitive letter; a letter that belongs to the radix.
One who advocates radical changes in government or social institutions, especially such changes as are intended to level class inequalities; -- opposed to conservative.
A characteristic, essential, and fundamental constituent of any compound; hence, sometimes, an atom.
Specifically, a group of two or more atoms, not completely saturated, which are so linked that their union implies certain properties, and are conveniently regarded as playing the part of a single atom; a residue; -- called also a compound radical. Cf. Residue.
The easiest way to get a reputation is to go outside the fold, shout around for a few years as a violent atheist or a dangerous radical, and then crawl back to the shelter. F. Scott Fitzgerald
The idea that UN commitments should be followed by action is indeed a radical one, especially for the United States, where wilful neglect of its own commitments is the rule. Jeffrey Sachs
The radical novelty of modern science lies precisely in the rejection of the belief... that the forces which move the stars and atoms are contingent upon the preferences of the human heart. Walter Lippmann
People often say that a bad event is a 'blessing in disguise.' Trust me, experience will teach you that some are unbelievably well disguised. Everyone gets fired, or decides to make a radical change at some point. Everyone suffers setbacks. Tom Freston
Only crime and the criminal, it is true, confront us with the perplexity of radical evil; but only the hypocrite is really rotten to the core. Hannah Arendt