Which term describes the fitting that keeps the watertight doors sealed?

The term that describes the fitting that keeps watertight doors sealed is 'gasket.' A gasket serves as a sealing component that creates a barrier to prevent the passage of water or air between the door and the frame, ensuring that the area remains watertight. In marine applications and various engineering contexts, maintaining a proper seal is crucial for the integrity of the structure, especially in environments exposed to water.

While hinges, seals, and latches contribute to the functionality and operation of watertight doors, they do not primarily serve the purpose of providing a watertight barrier like a gasket does. Hinges allow the door to pivot, latches secure it in place, and seals can refer to different types of closure mechanisms, but the specific role of creating a dependable seal against water ingress is the gasket's unique function. Thus, the gasket is essential for ensuring the watertight doors perform effectively in preventing leaks.