The creators of 'Viz' comic never knowingly fail to offend, and the spin-off 'Roger's Profanisaurus' is just as silly and tasteless. Simon Donald talks to Donald Clarke about making things up.

This generation's Samuel Johnson was born in Fulchester in 1947. Educated at Bartlepool Grammar and Oxford Remand Centre, our latter-day Noah Webster grew up to present TV shows such as Dirtbox Jury, Bastard World in Action and several others with titles we can't mention in a family paper.

He is, of course, Roger Mellie (the man on the telly), one of Viz comic's most enduring characters, and the new edition of his classic reference work, Roger's Profanisaurus, is on sale now. If, in the past, a senior colleague confounded you by explaining that he had to be excused because "Mr Brown is at the window" or you felt yourself embarrassed when the lady captain of the golf club wearily complained that "Arsenal are playing at home", then Mr Mellie's guide to filthy euphemisms is the book you need.

Viz creators Simon and Chris Donald had the idea for Roger when they overheard a Newcastle-on-Tyne TV presenter telling a dirty joke. As Simon Donald tells me: "My brother came up with this idea of a character who just can't tell the difference between his private life and his life on TV. So whatever celebrities are getting up to at the moment, Roger does that and just swears while he's doing it."

Sometimes this can be harmless enough. In this month's magazine, Roger finds himself on a version of I'm A Celebrity . . . Get Me Out of Here. But, as readers who remember Princess Diana: Ghost Private Detective of People's Heart will attest, the creators of Viz never knowingly fail to offend; the reference in the Profanisaurus's blurb to Roger's "accidental" strangling of his wife invites uneasy comparisons with the recent Michael Barrymore case.

Of course, being offended is clearly half the fun. Just as American writer P. J. O'Rourke's right-wing tub-thumping goes down well with liberals who enjoy the sheer naughtiness of it all, so too the frequent misogyny in Viz's pages offers forbidden pleasures to enlightened minds. Donald points out that Sinead O'Connor appeared at Glastonbury wearing a T-shirt depicting their unsightly radical feminist, Millie Tant. ("You have succumbed to femioppressive male-generated stereotypes." That's Millie speaking, not Sinead.)

But, to be fair, there is fantastic comic invention at work in the Profanisaurus. When Auberon Waugh famously compared the creators of Viz to Jonathan Swift he was over-egging the pudding a little, but literary Tourette merchants such as Chaucer or the Earl of Rochester would surely have recognised a kindred spirit in Roger. If only Rochester had the following definition to hand while writing his bawdy 17th-century verse: "Elvis's Leg n. The onset of the vinegar strokes whilst making love upright in a doorway, bus shelter or taxi queue. Often accompanied by an 'Uh-huh-huh' vocalisation and involuntary curling of the lip." (I have bowdlerised slightly).

The definitions often operate at several removes. The entry for "Take Captain Picard to warp speed" includes two further onanistic euphemisms: "strangle Kojak" and "pull Paul Daniel's head off".

Yet all this low-brow creativity is mostly coming from members of the public. "Profanisaurus is the thing we get most contributions for from the readers," Simon Donald explains. "But 90 percent of them go in the bin. Various reasons: we've had them before, they're just not funny, they've just made them up."

Hang on, the majority of the entries in the book must have been made up. Surely nobody actually refers to the "little indent above a builder's arse that holds about half a pint of sweat" as an arsevoir, do they?

"Well OK, sometimes we make things up because they sound right," he cackles. "For example, there's one that your readers might be particularly interested in that I made up myself. Air Lingus: A soft core . . ." You can imagine the rest, and you'll have to. Like I said, this is a family paper.

When any criticism is levelled at the material, Simon Donald falls back on the same technique that the writers have always used to counter accusations of poor taste or decline in standards: he further belittles the comic himself. "The majority of feminists have more sense than to complain about it," he says. "Because they realise that Viz is just childish."

They've been peddling this line since 1989, when the brothers began hawking the crudely photocopied first edition round Newcastle's pubs. Within months, Simon has claimed, people were suggesting it wasn't as funny as it used to be: Viz agreed. In the early-1990s, when each issue was selling a million copies, people said they had sold out: Viz agreed. Now that sales have declined somewhat (though it still shifts a healthy 200,000 copies), they put the phrase "Not as funny as it used to be (and it's losing sales)" on the cover. I don't buy this false modesty.

"Yes," he admits. "There is a thing where we pretend to be not proud of it: making out that it's just rubbish. But in our hearts we know that it's not true. It wouldn't have survived if it was just rubbish. It wouldn't be so popular if it was just rubbish."

Roger's Profanisaurus is published by Macmillan (£9.99 sterling)

Reviews appear on the Bulletin page