radical

noun

A person with radical opinions.

(arithmetic) A root (of a number or quantity).

(linguistics) 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 phonetic.

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

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

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

(organic chemistry) A free radical.

(algebra, commutative algebra, ring theory, of an ideal) 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.

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

(algebra, ring theory, of a module) The intersection of maximal submodules of a given module.

(number theory) The product of the distinct prime factors of a given positive integer.

(historical, 19th-century Britain, politics) A member of the most progressive wing of the Liberal Party; someone favouring social reform (but generally stopping short of socialism).

(historical, early 20th-century France) A member of an influential, centrist political party favouring moderate social reform, a republican constitution, and secular politics.

adjective

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

(botany, not comparable) Pertaining to a root (of a plant).

Pertaining to the basic or intrinsic nature of something.

Thoroughgoing; far-reaching.

(lexicography, not comparable) Of or pertaining to the root of a word.

(phonology, phonetics, not comparable, of a sound) Produced using the root of the tongue.

(chemistry, not comparable) Involving free radicals.

(mathematics) Relating to a radix or mathematical root.

(slang) Excellent; awesome.

Roots

radixradic- · Latin · root

Synonyms for radical

extremistadj revolutionaryadj ultraadj drasticadj reformistn revolutionistn progressiveadj leftistadj ultraconservativen reformern

Synonyms & related words for radical

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Words related to radical

Explore words related to radical — words associated with it, words that go with it, and its nearest matches in meaning. Related words include radicalness, chromyl, antiradical, radicalism, radically, univalent, tolyl, radicalize. Click any word to make it the center of the map and keep exploring the web of connections.

Synonyms for radical

Common synonyms for radical include extremist, revolutionary, ultra, drastic, reformist, revolutionist, progressive, leftist — words that share a close meaning. Hover or tap any word on the map for its definition and part of speech.

Where does radical come from?

The word radical breaks down into one root of Latin origin: the root radic-, from Latin radix (“root”). Explore each root to see other English words built from the same source.