radical.

Of or pertaining to the root of a plant.

Of or pertaining to the root of a word.

Produced using the root of the tongue.

Relating to a radix or mathematical root.

a radical quantity; a radical sign

Pertaining to the basic or intrinsic nature of something.

Favoring fundamental change, or change at the root cause of a matter.

His beliefs are radical.

Thoroughgoing; far-reaching.

The spread of the cancer required radical surgery, and the entire organ was removed.

Involving free radicals.

Excellent; awesome.

That was a radical jump!

A root (of a number or quantity).

In logographic writing systems such as the Chinese writing system, the portion of a character used to index it. Often, but not always, this is also the portion indicating meaning; compare the following sense. 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.

In logographic writing systems such as the Chinese writing system, the portion of a character used to index it. Often, but not always, this is also the portion indicating meaning; compare the following sense. Any component of a logographic character, whether used for indexing or not, whether semantic or not.

In Celtic languages, the basic, underlying form of an initial consonant which can be further mutated under the Celtic initial consonant mutations.

In Semitic languages, any one of the set of consonants (typically three) that make up a root.

A group of atoms, joined by covalent bonds, that take part in reactions as a single unit.

A free radical.

Given an ideal I in a commutative ring R, another ideal, denoted Rad(I) or √, 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.

Given a ring R, an ideal containing elements of R that share a property considered, in some sense, "not good".

The intersection of maximal submodules of a given module.

The product of the distinct prime factors of a given positive integer.

A member of the most progressive wing of the Liberal Party; someone favouring social reform (but generally stopping short of socialism).

A member of an influential, centrist political party favouring moderate social reform, a republican constitution, and secular politics.

A person with radical opinions.