'Radical' definitions:

Definition of 'radical'

(from WordNet)
adjective
(used of opinions and actions) far beyond the norm; "extremist political views"; "radical opinions on education"; "an ultra conservative" [syn: extremist, radical, ultra]
adjective
Markedly new or introducing radical change; "a revolutionary discovery"; "radical political views" [syn: revolutionary, radical]
adjective
Arising from or going to the root or source; "a radical flaw in the plan"
adjective
Of or relating to or constituting a linguistic root; "a radical verb form"
adjective
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" [syn: radical, basal] [ant: cauline]
noun
(chemistry) two or more atoms bound together as a single unit and forming part of a molecule [syn: group, radical, chemical group]
noun
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" [syn: free radical, radical]
noun
A person who has radical ideas or opinions
noun
(mathematics) a quantity expressed as the root of another quantity
noun
A character conveying the lexical meaning of a logogram
noun
(linguistics) the form of a word after all affixes are removed; "thematic vowels are part of the stem" [syn: root, root word, base, stem, theme, radical]

Definition of 'Radical'

From: GCIDE
  • Radical \Rad"i*cal\ (r[a^]d"[i^]*kal), n.
  • 1. (Philol.) (a) A primitive word; a radix, root, or simple, underived, uncompounded word; an etymon. (b) A primitive letter; a letter that belongs to the radix. [1913 Webster]
  • The words we at present make use of, and understand only by common agreement, assume a new air and life in the understanding, when you trace them to their radicals, where you find every word strongly stamped with nature; full of energy, meaning, character, painting, and poetry. --Cleland. [1913 Webster]
  • 2. (Politics) One who advocates radical changes in government or social institutions, especially such changes as are intended to level class inequalities; -- opposed to conservative. [1913 Webster]
  • In politics they [the Independents] were, to use the phrase of their own time, "Root-and-Branch men," or, to use the kindred phrase of our own, Radicals. --Macaulay. [1913 Webster]
  • 3. (Chem.) (a) A characteristic, essential, and fundamental constituent of any compound; hence, sometimes, an atom. [1913 Webster]
  • As a general rule, the metallic atoms are basic radicals, while the nonmetallic atoms are acid radicals. --J. P. Cooke. [1913 Webster] (b) 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. [1913 Webster]
  • 4. (Alg.) A radical quantity. See under Radical, a. [1913 Webster]
  • An indicated root of a perfect power of the degree indicated is not a radical but a rational quantity under a radical form. --Davies & Peck (Math. Dict.) [1913 Webster]
  • 5. (Anat.) A radical vessel. See under Radical, a. [1913 Webster]

Definition of 'Radical'

From: GCIDE
  • Radical \Rad"i*cal\ (r[a^]d"[i^]*kal), a. [F., fr. L. radicalis having roots, fr. radix, -icis, a root. See Radix.]
  • 1. Of or pertaining to the root; proceeding directly from the root. [1913 Webster]
  • 2. 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. [1913 Webster]
  • The most determined exertions of that authority, against them, only showed their radical independence. --Burke. [1913 Webster]
  • 3. (Bot.) (a) Belonging to, or proceeding from, the root of a plant; as, radical tubers or hairs. (b) 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. [1913 Webster]
  • 4. (Philol.) Relating, or belonging, to the root, or ultimate source of derivation; as, a radical verbal form. [1913 Webster]
  • 5. (Math.) Of or pertaining to a radix or root; as, a radical quantity; a radical sign. See below. [1913 Webster]
  • Radical axis of two circles. (Geom.) See under Axis.
  • Radical pitch, the pitch or tone with which the utterance of a syllable begins. --Rush.
  • Radical quantity (Alg.), a quantity to which the radical sign is prefixed; specifically, a quantity which is not a perfect power of the degree indicated by the radical sign; a surd.
  • Radical sign (Math.), the sign [root] (originally the letter r, the initial of radix, root), placed before any quantity, denoting that its root is to be extracted; thus, [root]a, or [root](a + b). To indicate any other than the square root, a corresponding figure is placed over the sign; thus, [cuberoot]a, indicates the third or cube root of a.
  • Radical stress (Elocution), force of utterance falling on the initial part of a syllable or sound.
  • Radical vessels (Anat.), minute vessels which originate in the substance of the tissues. [1913 Webster]
  • Syn: Primitive; original; natural; underived; fundamental; entire.
  • Usage: Radical, Entire. These words are frequently employed as interchangeable in describing some marked alteration in the condition of things. There is, however, an obvious difference between them. A radical cure, reform, etc., is one which goes to the root of the thing in question; and it is entire, in the sense that, by affecting the root, it affects in an appropriate degree the entire body nourished by the root; but it may not be entire in the sense of making a change complete in its nature, as well as in its extent. Hence, we speak of a radical change; a radical improvement; radical differences of opinion; while an entire change, an entire improvement, an entire difference of opinion, might indicate more than was actually intended. A certain change may be both radical and entire, in every sense. [1913 Webster]

Definition of 'radical'

From: GCIDE
  • Residue \Res"i*due\ (r?z"?-d?), n. [F. r['e]sidu, L. residuum, fr. residuus that is left behind, remaining, fr. residere to remain behind. See Reside, and cf. Residuum.]
  • 1. That which remains after a part is taken, separated, removed, or designated; remnant; remainder. [1913 Webster]
  • The residue of them will I deliver to the sword. --Jer. xv. 9. [1913 Webster]
  • If church power had then prevailed over its victims, not a residue of English liberty would have been saved. --I. Taylor. [1913 Webster]
  • 2. (Law) That part of a testeator's estate wwhich is not disposed of in his will by particular and special legacies and devises, and which remains after payment of debts and legacies. [1913 Webster]
  • 3. (Chem.) That which remains of a molecule after the removal of a portion of its constituents; hence, an atom or group regarded as a portion of a molecule; a moiety or group; -- used as nearly equivalent to radical, but in a more general sense. [1913 Webster +PJC]
  • Note: The term radical is sometimes restricted to groups containing carbon, the term residue and moiety being applied to the others. [1913 Webster]
  • 4. (Theory of Numbers) Any positive or negative number that differs from a given number by a multiple of a given modulus; thus, if 7 is the modulus, and 9 the given number, the numbers -5, 2, 16, 23, etc., are residues. [1913 Webster]
  • Syn: Rest; remainder; remnant; balance; residuum; remains; leavings; relics. [1913 Webster]

Synonyms of 'radical'

From: Moby Thesaurus