Spy novel aficionados should be plenty familiar with our current term, as it seems every Whitehall spook out of Graham Greene, John LeCarré and Len Deighton wore a suit or coat made from it. Invented in 1879 by Thomas Burberry (yep, the trench coat guy) and named after a type of cloak worn during the middle ages, gabardine is renowned for being naturally water-resistant. This is thanks to the closeness of its weave construction, which involves many more warp yarns than weft ones and which results in sufficient surface tension to cause water to bead upon hitting it and roll off before it can seep in. These days, of course, there are any number of synthetics to shield you from the elements (including neoprene, which Burberry designer Christopher Bailey famously transformed into multicolored trench coats a few seasons back). But then, if gabardine was good enough for Ernest Shackleton on his famous expedition to Antarctica, it ought to be sufficient to keep you dry on your morning commute.