ass gasket

Noun.
History: Believed to be a Gallagher-ism (American comic of 1980s & 1990s known mostly for pulverizing melons w/a huge slegehammer in his shows).
Definition: Those wisp-thin, slightly waxy paper toilet seat covers offered in public toilets to protect one's bodunkadunk from coming in contact with someone else's funk.
> When using the toilet at the Port Authority Bus Terminal, always put an ass gasket down before you cop a squat.