petcock

Example:The valve was closed to prevent any fuel from escaping the tank.

Definition:A device for regulating, controlling, or interrupting the flow of a liquid or gas by opening, closing, or partially obstructing various passageways.

Example:The lid was tightly secured to ensure the fuel tank remained airtight.

Definition:The top part of a container, often flat and sealing to keep contents inside or out.

Example:A seal was applied to the fuel tank lid to ensure the container was airtight and secure.

Definition:Something that fastens or closes a container by preventing contents from leaking out or foreign objects from entering.