What is (a) A couch for reclining at meals, extending round three sides of a table, and usually in three parts. (b) A dining room furnished with such a triple couch called?

triclinium — (a) A couch for reclining at meals, extending round three sides of a table, and usually in three parts. (b) A dining room furnished with such a triple couch. (Webster's 1913.)

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