coaster

from WordNet (r) 3.0 (2006)

coaster
    n 1: a resident of a coastal area
    2: someone who coasts
    3: a covering (plate or mat) that protects the surface of a
       table (i.e., from the condensation on a cold glass or bottle)

from The Collaborative International Dictionary of English v.0.48

Coaster \Coast"er\, n.
   1. A vessel employed in sailing along a coast, or engaged in
      the coasting trade.
      [1913 Webster]

   2. One who sails near the shore.
      [1913 Webster]

from Jargon File (4.4.4, 14 Aug 2003)

coaster
 n.

   1. Unuseable CD produced during failed attempt at writing to writeable
   or re-writeable CD media. Certainly related to the coaster-like shape
   of a CD, and the relative value of these failures. "I made a lot of
   coasters before I got a good CD."

   2. Useless CDs received in the mail from the likes of AOL, MSN, CI$,
   Prodigy, ad nauseam.

   In the U.K., beermat is often used in these senses.

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