Andrew Martin: 'Laters, bruv', and off they go in mummy's 4x4

A surprise big seller of the Christmas book market is The A-Z of Teen Talk. I showed my youngest son who will be a teenager himself in four months' time a selection of the words contained. He'd heard of some, disagreed over the definition of others: "Is this slang of the 1980s?" he sneered. "Is it, like, written by a 50-year-old man?"

I informed him with some satisfaction that the author, Lucy van Amerongen, is 13 and therefore well qualified to assert that "butters" is part of a composite teenage goodbye, as in "Laters, butters" (even though my son thinks that "butters" just means bad), and that the young people of today as they were called in the distant past abbreviate "pizza" to "za", and that "mouldies" are parents, and so on.

My son's reaction had been defensive, territorial, and this was quite in keeping, since teen-speak is seen by teenagers as part of a battle. Each new coinage is a grenade lobbed into the language, especially in the inversion of old meanings. First there was "wicked" for "good", but that is "old school", and now my sons say "sick" to mean good. I do not think this will catch on among the mouldies, but my sons will stop using it if it does.

I am 45 and I divide my contemporaries into those willing to talk like their children, and those who constantly correct them. I first heard the rhetorical question, "How cool is that?" when Ben Elton used it at a gig in the early 1990s. I thought: that's horrible and creepy; I hope I never hear that again. Now about half of my friends say it, and all of their children.

Some of my friends drink their coffee from mugs labelled things like "Cool Daddy", and these types are likely to have the "like" disease, which is the linguistic equivalent of having acne at 45. Both my sons have it, and they interpolate the word particularly often when in adult company with me. They enjoy seeing the redness of anger rising in my face. I wonder if I could put them off by telling them it was originally associated with girls' talk. (An internet trawl unearths this from an American educationalist, Professor William L Bainbridge: "It must have started somewhere in the cheerleading camp, and spread ... with the help of the early 1980s song and movie Valley Girl.")

That might work, since there's a lot of machismo in the teen-talk of boys, not least in their use of "gay" to mean generally crap one of the few aspects of young-speak deplored, as opposed to embarrassingly co-opted by, the liberal press. The corridors of our public schools echo with black street-talk, and fifth-formers take their leave of each other with, "Laters, bruv", before climbing into mummy's 4x4.

I tell myself I do not resent teenage-speak so much as the naivety of the premise behind it. It does not truly signify rebellion in 2008. There is a vast industry encouraging a distinctive teenage culture, and my sons remind me that they've been co-opted into it every time they say the word "cool" (which according to Van Amerongen is now being replaced by "nang").

But I can't deny the potency of their vocabulary, its power to enrage. If I hand one of my sons his pocket money and he says "Safe" instead of thanks, I'll give him a lecture.

But, like all his generation, he has been furnished probably by the adults owning the "Cool Daddy" mugs with the standard liberal response: "The language is constantly evolvin', Dad. Catch up."