Colours are taken very seriously by underwear experts - not least because describing them accurately and repeatedly is one of the toughest jobs we do.

As partner Jane Garner, who is also a fashion journalist, explains: "You don't just see colour with your eyes, but with your brain, which is why the same car painted red will appear to travel faster than the same model in blue, even when they both go past at exactly the same speed."

The challenge at DGU is to convey not just a colour, but a shade, a finish, and combine that with the feel of the fabric in a pair of boxers or briefs, a swimshort or swimming slip. "A matt cotton blue will have a very different appeal compared to a similar shade in a slinky microfibre," says Jane.

"So we were very interested to read about the world's first thesaurus of colour names. This is an epic undertaking which should be applauded - but the drawback is that people see the same hue differently and translate colour terminology very differently too. So, what IS egg yolk and how is that different from primrose, banana or sunshine yellow?"

Jane and Deadgoodundies have often given teenagers work experience training and one of their tests is the infamous Colours List.

"We have a standard list of simple colour names from black and white to red, blue, purple, brown etcetera and we challenge them to come up with at least three terms for each. This is how we ended up one year with nominations for Bacon Pink and Jam Red. I'm not sure our customers would find pink underpants likened to bacon very appealing, and we do try to be specific, so what flavour jam would this red really be...?" says Jane, who is blessed with a keen eye for colour.

"If there's any debate about what to call a particular colour, I'm called on to make sure we're consistent in Deadgoodundies descriptions. I'm also often invited on girlfriends' shopping trips for new clothes because I remember the exact shade of green or blue or navy (there are endless navies!) they're trying to match."

Some might dispute the idea that men are alert to colour differences, but Jane and DGU partner Adam Davies are often wary of certain tones that never sell well, she explains: "Some greens and orange can be tricky, customers in different countries will often buy more of a certain colour, such as maroon or petrol blue, and what men will wear as underwear is poles apart from the colourful combinations they will don to go on the beach!"

Deadgoodundies stocks hundreds of colours in thousands of interpretations by shade, finish, fabric, often contrasting with trim and in prints. Even the scale on which a colour is used will influence its selling power - red or blue briefs and boxers work just as well, while yellow, gold and silver are favoured in smaller pieces, greens are very personal and orange men's underwear is always individual. Even minimalist white translates in different ways on vests and tops, tiny g-strings and classic buttoned boxers or long johns.