An oilskin is a waterproof garment, typically worn by sailors and by others in wet areas, such as fish-plant workers. Originally handmade of sailcloth waterproofed with a thin layer of tar, they were later (early 1930s) mass-produced of canvas duck coated with multiple applications of linseed oil (oilcloth) and often finished with layers of paint.
While most modern oilskins are made of flexible PVC-coated synthetic fabric, advanced materials for extreme conditions such as yacht racing are increasingly employed. Also known as "foul weather gear", contemporary oilskins include such innovations as DWR-coated nylon on their low end and Gore-Tex and other proprietary waterproof membranes on the high.
A Sou'wester, a traditional form of collapsible oilskin rain-hat, is longer in the back than the front to fully protect the neck. Sou'westers sometimes feature a gutter front-brim.
Today's oilskins (or oilies) typically come in two parts, jackets and trousers. Oilskin jackets are generally similar to common rubberized waterproofs. The chief difference is a high spray collar. Some have hoods, often in a high-visibility colour to increase visibility if a wearer falls overboard. Retroreflective patches are also strategically placed, and jacket tails are extra long to keep water off the legs and out of the joint where waterproof trousers meet.
Oilskin trousers - also known also as "bibs" - are very high-cut to provide a large overlap with the jacket. They are held up by shoulder straps, and typically feature straps around the bottom of the legs to cinch around seaboots. This semi-watertight seal does not allow them to be used like fishing waders, but a wave sweeping briefly across the deck will generally be kept out. All but the cheapest brands are reinforced across the seat and knees.