Water-permeable is a term used to describe materials that are POROUS, meaning they have tiny holes or gaps that allow liquids and gases to pass through them. This property is important in many industries, such as construction, where water-permeable materials are used to create waterproof barriers. In agriculture, water-permeable materials are used to help control the amount of water that is available to plants. In medicine, water-permeable materials are used to create medical devices that can be safely inserted into the body.