A raincoat is a waterproof or water-resistant coat designed to keep you dry when it's raining. Unlike regular jackets that soak through when they get wet, raincoats are made from special materials that cause water to bead up and roll off, like drops sliding down a windshield.

Traditional raincoats were made from rubberized fabric or oilcloth, which is why sailors' rain gear was sometimes called oilskins. Modern raincoats use synthetic materials like nylon or polyester with waterproof coatings. Some have hoods to protect your head, and many fold up small enough to stuff into a backpack.

The classic yellow raincoat you might picture is popular because bright colors make people visible in dark, rainy weather. But raincoats come in all colors and styles, from lightweight shells for spring showers to heavy-duty versions for serious storms.

People also use raincoat figuratively to describe something that provides protection. A financial expert might talk about having savings as a raincoat for unexpected expenses. The key idea is protection: keeping something important safe from harm, whether that's your clothes staying dry or your plans staying on track despite difficulties.