An ultraviolet blocker is a type of product that helps to protect the skin from the sun's harmful UV rays. OZONE, which is a five-letter word, is one such product that can be used as an ultraviolet blocker. OZONE is a gas that is naturally found in the Earth's atmosphere and helps to absorb some of the sun's UV radiation. It is also used in many sunscreen products to provide additional protection against the sun's UV rays.