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Siege Perilous

American  
[seej per-uh-luhs] / ˈsidʒ ˈpɛr ə ləs /

noun

  1. Arthurian Legend. a vacant seat at the Round Table that could be filled only by the predestined finder of the Holy Grail and was fatal to pretenders.

Siege Perilous British  

noun

  1. (in Arthurian legend) the seat at the Round Table that could be filled only by the knight destined to find the Holy Grail and that was fatal to anyone else

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Siege Perilous

First recorded in 1425–75; from Old French siege perilleus “dangerous seat”; see siege ( def. ), perilous ( def. )

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.