Other forms: coasters
A coaster is the little mat you stand a glass on so the table does not end up with a ring. Cork, cardboard, slate, or the brewery-branded ones stacked at the end of a pub table.
It is also short for roller coaster, so 'we rode every coaster in the park' is about rails and screaming, not drinks. In shipping, a coaster is a small vessel that works its way along the coast instead of crossing oceans. The verb behind all of it, coast, means to roll along without power: you coast downhill on a bike, and you coast through an easy year at work. In a British pub the cardboard one is a beer mat; coaster is the word for the cork or wooden one at home.
1nouncoasterA small mat that a drink stands on to protect the surface underneath.
“Use a coaster or you'll leave a mark on the table.”
synonyms: beer mat, drinks mat
2nounrollerA roller coaster.
“The new coaster has a hundred-foot drop.”
3nounshipA ship that trades along a coast rather than across open sea.
“The harbour was busy with small coasters loading timber.”
coaster is a small mat.
Coaster is coast plus the ending -er. Coast itself came through Middle English coste from Old French coste and Latin costa, which meant rib and then side — the coast is the land's side, and a coaster is the ship that keeps close to it. The same Latin costa is still in medical English as costal, meaning anything to do with the ribs.
Latin
costa — rib; side, wall
Old French
coste — rib; side of an object; coast
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
English, today
coaster
From coast + er. 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”)coest, cost, coost, cooste, kost, koste, from Old French coste (“rib; side of an object; coast”) (modern French côte (“rib; coast; hill, slope”)), from Latin costa (“rib; side, wall”).
Etymology from Wiktionary, CC BY-SA