radical

In chemistry, an atom or group of atoms carrying an unpaired electron, which is therefore highly reactive and often impossible to purify or keep for any length of time.

A radical can either recombine with another radical (creating an electron pair and thus a stable compound) or attack a stable molecule and thereby create a new radical and start a chain reaction. However, organic chemists can create reasonably stable radicals by surrounding the atom carrying the unpaired electron with bulky molecular groups that block or slow down its reaction.

Ozone is a radical, as are some of the chlorine compounds that are liberated from organic pollutants and start the chain reactions that ultimately damage the ozone shield.

Radical

In Britain, supporter of parliamentary reform before the Reform Bill of 1832. As a group the Radicals later became the progressive wing of the Liberal Party. During the 1860s (led by Cobden, Bright, and J S Mill) they campaigned for extension of the franchise, free trade, and laissez-faire, but after 1870, under the leadership of Joseph Chamberlain and Charles Dilke, they adopted a republican and semi-socialist programme. With the growth of socialism in the later 19th century, Radicalism ceased to exist as an organized movement.

In France, the Radical Party was a major force in the politics of the Third Republic, 1871–1940.

The radical may be said to have been the product of the ideas germinating in Europe from the philosophy of Rousseau after the French Revolution, and partly an inevitable outcome of the growth of industrial society. The name radical reformer appears first to have been assumed by Hunt, Cobbett, and others, who were intent on influencing the people in the direction of great and popular constitutional changes. By the time of the first Reform Bill of 1832 the Radicals had gained a definite and permanent footing in the House of Commons, where they were represented by at least 55 members. From this time forward the term became gradually interchangeable with ‘Liberal’.

radical

In politics, anyone with opinions more extreme than the main current of a country's major political party or parties. It is more often applied to those with left-wing opinions, although the radical right also exists.

In politics, the term came into general use as a synonym for ‘liberal’, but is capable of application to any politician or political supporter whose political creed involves some root- and-branch reform.

In recent years the meaning of the term has changed, since radical outlooks have emerged that are no longer identifiable with liberal, socialist, or communist policies; for example, the various ‘New Left’ trends and ‘sexual radicals’.