What do radicals and radishes have in common?

How much do Omar Bakri Muhammad and Abu Hamza have in common with Richard Cobden and John Bright

There is a word that links Muslim militants, Victorian reformers and crispy salad vegetables, writes Trevor Timpson.

"Radicalisation taking place across the UK," says the Commons Home Affairs committee chairman, "is reaching unprecedented levels." The term "radical" for many has come to mean just "extremist". But its long history has honourable associations.

Radix in Latin means root and since the time of Cicero has been used figuratively for the basis, foundation or essence of something. "Let us dare," wrote the orator about 45BC, "not only to cut off every branch of our misery, but also to dig out every fibre of its roots (omnes radicum fibras)."

It was easy to apply such imagery to politics, though this did not happen in English until the late 18th Century. In 1793 the campaigners of the London Corresponding Society presented a petition to the Commons "praying for a radical reform in the representation of the people".

"Radical" described the established order - not its critics - the "radical system of despotism" which "radical reform" was to change.

From "radical reform" those wanting change became "radicals" - recognisably people of the "left" and generally in favour of extending the right to vote.

Though what else they called for could change, well, radically. The radical statesmen Richard Cobden and John Bright, for instance, were campaigners for the free market. Not a "radical" cause today.

Cobden and Bright were deeply respected, even by opponents. Schools and streets are still named after them. After Bright's death in 1889 Tory Prime Minister Lord Salisbury lauded the oratory with which he expressed his "burning and noble thoughts".

Later "radical" came to be applied not to reformers, but to ultra-conservatives. Seymour Lipset coined the term "radical right" in 1955 because he said it "desires to make far-reaching changes in American institutions".

And some commentators prefer the term "radical Islam" to "fundamentalism" because they contest the claim that fundamentalists are "returning to some historic norm of practice".

Radish also comes from radix - though its route into English is uncertain. It may be one of a few Latin words that came into Anglo-Saxon early.

Certainly the word redic or raedic appears in Anglo-Saxon. But some experts believe the current form came to English from French or Provençal.

There is a term "radish communist" - said to have been used by both Trotsky and Stalin - for someone who espouses communism without believing in it.

Red outside, white inside. Like a radish - but perhaps not radical.

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