oilskin

noun

1. (countable, uncountable)Cloth made from cotton and treated with oil and pigment to make it waterproof.
2. (countable, uncountable)A raincoat made from cotton fabric treated with oil and pigment to make it waterproof.

   “I noticed Larry to-day had on two vests, two coats, and an overcoat with his oilskin outside of that.”

   “He was preparing to venture out again, when Gaskin opened a locker and brought out an oilskin. “Hit'll 'elp you keep dry, sir,” holding up the garment.”

3. (broadly, countable, uncountable)Foul-weather gear worn by sailors, whether of natural or synthetic materials.