"Hey homeboy, this rocket and watercress salad is safe blood, you get me?" Mrs Bogof said to me the other day in the salad aisles of Tesco.

While my wife has been known to get down with the kids (her high score on Grand Theft Auto is legendary) she is not known for her street slang. It turns out, however, that she has got her hands on a new booklet being distributed to some of the "more mature" members of Tesco's staff to help them keep up with what the supermarket calls 'street speak'.

The guide was drawn up by a panel of teenagers recruited by Tesco's head office. Among the phrases in the book are 'A and B the C of D', which apparently means above and beyond the call of duty; 'am I bovvered?', which Tesco translates as 'quite frankly I don't care'; and 'homeboy', which is a person 'who is there for you like a brotha' (sic) it says. Probably the most confusing phrase is 'bad', which Tesco helpfully says means good, but can also mean bad. When in doubt, it suggests you just smile and nod. It sounds like some of the staff dig the new lexicon. "We had great fun trying this out with the younger lads in store," says one. "It's a good - or should I say 'bad' idea."

I, for one, definitely think it's a bad idea, as I told Mrs Bogof. She just smiled and nodded.