Watertight refers to something that is sealed or closed in such a way as to prevent water from entering it. This term can be used to describe various objects, including containers, buildings and even electronic devices. When an object is described as watertight, it means that it has been designed and constructed in a manner that prevents the passage of water through any openings or seams. Watertight materials are often used in marine applications, such as boats and shipbuilding, to ensure that the interior remains dry even when submerged in water. In summary, watertight refers to something that is completely impervious to water, meaning it cannot be penetrated by liquid.