gasket

Short definition from Wiktionary

Noun

1. 1
   A length of rope or canvas band 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.

Verb

1. 1
   To fit a gasket
2. 2
   To seal wth a gasket