Radical

English

radical

Of or pertaining to the root or root cause of the matter.
Thorough going or fundamental.
The spread of the cancer required radical surgery, and the entire organ was removed.
Favouring fundamental change, or change at the root cause of the matter.
His beliefs are radical.
Slang: Extremely, incredible: That was a radical jump!

radical

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Radical

Person with radical opinions.
(Hist. - 19th-century England) A member of the most progressive wing of the Liberal Party; someone favouring social reform (but generally stopping short of socialism).
(Hist. - Early 20th-century France) A member of an influential, centrist political party favouring moderate social reform, a republican constitution, and secular politics.
((mathematics{{#if:|, {{{2}}}{{#if:|, {{{3}}}{{#if:|, {{{4}}}{{#if:|, {{{5}}}{{#if:|, {{{6}}}{{#if:|, {{{7}}}{{#if:|, {{{8}}}{{#if:|, {{{9}}}}}}}}}}}}}}}}}}})) The root of a quantity n as notated by √n.
(linguistics) In Chinese (and other logogram based languages), that portion of a character that provides an indication of its meaning. This may be the whole character, or just a small part of it. See also phonetic.
((chemistry{{#if:|, {{{2}}}{{#if:|, {{{3}}}{{#if:|, {{{4}}}{{#if:|, {{{5}}}{{#if:|, {{{6}}}{{#if:|, {{{7}}}{{#if:|, {{{8}}}{{#if:|, {{{9}}}}}}}}}}}}}}}}}}})) A group of atoms, joined by covalent bonds, that take part in reactions as a single unit.