radical

adjective more radical · most radical

1. not comparable Of or pertaining to the root of a plant.
2. not comparable Of or pertaining to the root of a word.
3. not comparable, of a sound Produced using the root of the tongue.
4. Relating to a radix or mathematical root. a radical quantity; a radical sign
5. Pertaining to the basic or intrinsic nature of something. The most determined exertions of that authority, against them, only showed their radical independence.

   Similar: fundamental · Opposite: ignorable, trivial

6. Favoring fundamental change, or change at the root cause of a matter. His beliefs are radical.
7. Thoroughgoing; far-reaching. The spread of the cancer required radical surgery, and the entire organ was removed.
8. not comparable Involving free radicals.

   Similar: primitive

9. slang Excellent; awesome. That was a radical jump!

   Similar: rad

Similar: Jacobin, Jacobinic, Jacobinical · Opposite: derivative, derived

noun radicals

1. A root (of a number or quantity).
2. In logographic writing systems such as the Chinese writing system, the portion of a character (if any) that provides an indication of its meaning, as opposed to being wholly phonetic.

   Similar: semantophore

3. common, proscribed Any component of a logographic character, whether used for indexing or not, whether semantic or not. The boy recognised the Chinese characters, though the calligraphy looked a bit strange, as if drawn by someone who had seen them and copied them out radical by radical without knowing what they meant.

   Similar: component

4. In Celtic languages, the basic, underlying form of an initial consonant which can be further mutated under the Celtic initial consonant mutations.
5. In Semitic languages, any one of the set of consonants (typically three) that make up a root.
6. A group of atoms, joined by covalent bonds, that take part in reactions as a single unit.
7. A free radical.
8. of an ideal Given an ideal I in a commutative ring R, another ideal, denoted Rad(I) or √I, such that an element x ∈ R is in Rad(I) if, for some positive integer n, xⁿ ∈ I; equivalently, the intersection of all prime ideals containing I.
9. of a ring Given a ring R, an ideal containing elements of R that share a property considered, in some sense, "not good".
10. of a module The intersection of maximal submodules of a given module.
11. The product of the distinct prime factors of a given positive integer.
12. historical A member of the most progressive wing of the Liberal Party; someone favouring social reform (but generally stopping short of socialism).
13. historical A member of an influential, centrist political party favouring moderate social reform, a republican constitution, and secular politics.
14. A person with radical opinions.