| 释义 |
rad·i·cal
I. \ˈradə̇kəl, -dēk-\ adjective
Etymology: Middle English, from Late Latin radicalis, from Latin radic-, radix root + -alis -al — more at root
1. : of or relating to the root : proceeding directly from the root: as
a.
(1) : of or proceeding from the root of a plant
< radical tubers >
(2) : proceeding from the base of a stem, from a rootlike stem, or from a stem that does not rise above the ground
< radical leaves >
— compare cauline
b. : of, relating to, or constituting a linguistic root
< a radical verb form >
c. : of or relating to the root of a nativity or an election in astrology
d. : of or relating to a mathematical root
e. : designed to remove the root of a disease or all diseased tissue
< radical surgery >
— compare conservative
2. : of or relating to the root or origin : original : fundamental : inherent
< differences that may be ascribed to radical peculiarities of mind — Robert Bridges †1930 >
< the radical trouble is that man is by nature a liar — Henry Adams >
< radical differences in English and Navaho language structure — J.B.Carroll >
< her radical unfitness for an ascetic regimen — George Santayana >
< reacting against the radical faults of man and society — C.W.Hendel >
3.
a. : marked by a considerable departure from the usual or traditional : extreme, thoroughgoing, drastic
< the most radical proposals have called for the abandonment of the bicameral system — A.N.Holcombe >
< to seek education for women at a time when the idea was considered a dangerously radical doctrine — Current Biography >
< the radical music written between 1910 and 1930 — New Republic >
b. : tending or disposed to make extreme changes in existing views, habits, conditions, or institutions
< observation will reveal many people who are radical in politics and conservative in religion — D.D.McKean >
< the truly radical party, the party of the destroyers of traditional values — New Republic >
c. : of, relating to, or constituting a political group associated with views, practices, and policies of extreme change: as
(1) usually capitalized : of, relating to, or constituted by the British radicals of the 19th century
(2) usually capitalized : of, relating to, or constituted by the Radical Republicans
Synonyms: see liberal
II. noun
(-s)
1.
a. : a root part
< some radical of our being which is persistent — H.B.Alexander >
b. : basic principle : basis, foundation, support
2.
a. : an uncompounded word or element without prefix, infix, suffix, or inflectional ending : root
b. : a sound or letter belonging to a radical; especially : an original unchanged initial consonantal sound in Celtic languages or one of the three original consonants forming the triliteral roots in Semitic languages
c. : one of 214 Chinese characters that represent categories of sense and are combined with phonetics to form phonograms whose meaning they suggest
3.
a. : a radical expression in mathematics
< the expression n√a is called a radical of order n — R.S.Underwood & F.W.Sparks >
b. : radical sign
4. : one that is radical: as
a. : one that advocates a decided and often extreme change from existing, usual, or traditional views, habits, conditions, or methods
< a literary radical at heart, he was fighting … for a reevaluation of values — R.E.Spiller >
< regarded as something of a radical in anthropological circles … when he proposed that Neanderthal man might be classified as Homo sapiens — R.W.Murray >
< the young radicals … who met regularly to discuss the new musical theories — Edward Sackville-West & Desmond Shawe-Taylor >
b. : one that advocates radical and sweeping changes in laws, institutions, and methods of government with the least delay: as
(1) : a member of the extreme wing of the British Liberal party in the 19th century
(2) : a member of a group in the North favoring extreme measures against the South during the Civil War
(3) : a member of a group in the North favoring a policy of reconstruction in the South after the Civil War
5. [French, from radical, adjective, from Late Latin radicalis] : a fundamental constituent of a chemical compound:
a. according to Lavoisier : the part of an acid that does not contain oxygen and that in combination with the acidifying principle oxygen constitutes the acid
b. : a single replaceable atom of the reactive atomic form of an element
c. : a group of atoms that is replaceable by a single atom or that is capable of remaining unchanged during a series of reactions, that need not be isolable (as acetyl, tertiary butyl, methylene, cyanogen, hydroxyl) but that sometimes is isolable, or that may show a definite transitory existence in the course of a reaction
III. adjective
slang : cool 8 : excellent
IV. noun
: free radical |