gasket

noun

1. 1.A length of rope used for reefing a sail, or holding a stowed sail in place.
2. 2.Any mechanical seal that serves to fill the space between two objects, generally to prevent leakage between the two objects while under compression.
3. 3.A material which may be clamped between faces and acts as a static seal. Gaskets may be cut, formed, or molded to the desired configuration.
4. 4.Any of a wide variety of seals or packings used between matched machine parts or around pipe joints to prevent the escape of a gas or fluid.