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coaster

n.
US //ˈkoʊstɝ// UK //kˈəʊstɐ// coast·er
  1. 1 mat for a drink (n.)
    B1 Intermediate

    a small mat or piece of wood that you put under a glass or cup to protect the table.

    a small tray or mat, often made of cork, wood, or plastic, placed under a drinking vessel to protect the surface of a table from moisture or heat.

    Example

    Please use a coaster so you do not leave a ring on the wooden coffee table.

    Example

    The host provided marble coasters to ensure that the chilled cocktails did not leave condensation marks on the antique mahogany desk.
  2. 2 theme park ride (n.)
    B1 Intermediate Informal

    a short name for a roller coaster, which is a fast ride at an amusement park.

    a common clipping of 'roller coaster', referring to an elevated railway with steep inclines and sharp curves found in amusement parks.

    Example

    The new coaster at the theme park is the tallest and fastest in the country.

    Example

    Adrenaline seekers queued for hours to experience the park's newest coaster, which featured a record-breaking vertical drop and multiple inversions.
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  1. 3 coastal ship (n.)
    B2 Upper Intermediate Technical Nautical

    a ship that carries goods between ports along the same coast.

    a merchant vessel designed for trading along a coast rather than making transoceanic voyages.

    Example

    The small coaster delivered coal to several towns along the northern shore.

    Example

    The harbour was crowded with small coasters and fishing boats, all seeking shelter from the gale-force winds predicted for the channel.
    • coastal vessel
  2. 4 one who puts in little effort (n.)
    C1 Advanced Informal

    a person who does just enough work to get by without trying hard.

    an individual who exerts the minimum effort required to maintain their position or progress, effectively 'coasting' through tasks.

    Example

    He used to be a top student, but lately he has become a bit of a coaster.

    Example

    Management identified several coasters in the department who were relying on the momentum of the team rather than contributing to the new project.
    • overachiever
    • striver
  3. 5 failed CD or DVD (n.)
    C2 Proficiency Slang Computing

    a CD or DVD that did not record correctly and is now useless.

    a slang term for a recordable optical disc that has been rendered useless by a write error during the burning process.

    Example

    The power went out while I was burning the disc, so now it is just a coaster.

    Example

    Before high-speed internet became standard, a single buffer underrun could turn an expensive blank media disc into a shiny plastic coaster.

    Usage

    Usually refers to the physical disc being good for nothing but use as a drink coaster.

Etymology 1

From coast (“edge of the land where it meets an ocean, sea, gulf, bay, or large lake”) + -er (suffix forming agent nouns). Coast is derived from Middle English coste (“rib; side of the body, flank; side of a building; face of a solid figure; coast, shore; bay, gulf; sea; concavity, hollow; boundary, limit; land; country; district, province, region; locality, place; division of the heavens; compass direction; direction; location with reference to direction, side”) [and other forms], from Old French coste (“rib; side of an object; coast”) (modern French côte (“rib; coast; hill, slope”)), from Latin costa (“rib; side, wall”).

Etymology 2

From coast (“to glide along without adding energy; to make a minimal effort; to slide downhill (especially, to slide on a sled upon snow or ice)”) + -er (suffix forming agent nouns). Coast is derived from Middle English costeien (“to travel along a border or coast; to go alongside (something), skirt; to accompany, follow; to travel across, traverse; to be adjacent to, to border;”) [and other forms], from Anglo-Norman [Term?], Old French costoier (“to be at the side of”) [and other forms] (modern French côtoyer (“to pass alongside; (figuratively) to rub shoulders”)), from Latin costicāre, from costa (“rib; side, wall”); see further at etymology 1. etymology 2 sense 2.1 (“small stand or tray”) is from the fact that the object and the decanter or wine bottle on it “coast” or travel around a tabletop from person to person. etymology 2 sense 2.2.2 (“useless compact disc or DVD”) refers to the fact that the object is only useful as a drink coaster. etymology 2 sense 2.5 (“minibus”) is a genericized trademark from Toyota Coaster. Compare Spanish coaster / cúster.

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