Excalibur is defined as was the name of King Arthur's sword.(noun)
An example of Excalibur is the sword that, according to legend, King Arthur pulled from a stone.
See Excalibur in Webster's New World College Dictionary
Origin: ME < OFr Escalibor < ML Caliburnus < Celt
See Excalibur in American Heritage Dictionary 4
Origin: Middle English
Origin: , alteration (perhaps influenced by Latin chalybs, steel)
Origin: of Medieval Latin Caliburnus
Origin: , from Middle Welsh Caletuwlch
Origin: or Middle Irish Caladbolg, a legendary sword.
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