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Yet despite the increasing trend for television and radio programmes - and advertising campaigns - to push the linguistic boundaries, it would seem that Britons would prefer to keep it clean.

According to a survey on attitudes to "bad language", the use of swear words and terms of abuse before the 9pm watershed is unacceptable to most adults.

The survey, issued jointly by the BBC, the Broadcasting Standards Commission, the Independent Television Commission and the Advertising Standards Authority, found that gratuitous swearing turned viewers off.

In keeping with the BBC's guidelines on taste and decency, it has been left up to the gentle reader to guess which four-letter words topped the study's list of offensive terms.

Yet while words such as "shag" are thought to be less naughty today than in a similar study two years ago, terms of racist abuse are now more offensive.

Contrary lot that we viewers are, shock value lies less in the word actually used than in its context and frequency.

Although three-quarters of the 1,033 adults questioned had no problem with expletives uttered "in shock", the same proportion didn't like swear words used as a matter of routine.

Linguistic wallpaper

Jonathon Green, author of the Cassell Dictionary of Slang and The Big Book of Being Rude, says words that hold the power to shock are changing.

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Over the past 500 years, swearing has gone through three phases, the third of which only began 10 years ago.

"Some 500 years ago in the Western world, religion mattered - the majority of people believed in religion and believed in God. Therefore the words and phrases deemed offensive were blasphemous.

"By the 19th Century, religion was losing its grip and words that had once been standard - words to do with sex and bodily functions - were beginning to be taboo."

But today, many of these swear words have become debased because they are so commonly used.

Whereas the Channel 4 comedy Father Ted softened its liberal use of f*** by substituting an "e" for "u", films such as South Park have dispensed with such niceties all together.

Viewers may not find such language offensive themselves, but may well object if children or the elderly cop an earful, Mr Green says.

Racist slang

Derogatory words are now slang terms used to describe those perceived as different, Mr Green says.

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Thus, people who use the f-word freely and frankly will shy away from saying "spastic" or "Paki" - derogatory terms deemed too offensive for TV and radio by the majority of survey respondents.

Using racial - or cultural - differences to denigrate others is a long-standing habit of human nature, Mr Green says.

Throughout the ages, the colonised have turned the characteristics of their conquerors into insults.

"Often it is to do with what the colonisers eat. The French, for example, were referred to as 'frogeaters'."

Good manners?

Mr Green challenges the idea that sanitising language is good manners: "It's not, it's hypocrisy."

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As someone who embraces so-called swear words as part of the English language's rich tapestry, what does he find offensive?

"I personally find it distressing that 'gay' has become a playground taunt," Mr Green says.

"Damilola Taylor, the boy killed in Peckham two weeks ago, was reportedly taunted in this way.

"At 10, I doubt he would have had much understanding of sexuality, so there's something quite grotesque about that."