E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Properly divided, it is sang-real, the real blood of Christ, or the wine used in the last supper, which Christ said was His blood of the New Testament, shed for the remission of sin. According to tradition, a part of this wine-blood was preserved by Joseph of Arimathæa, in the cup called the Saint Graal. When Merlin made the Round Table, he left a place for the Holy Graal. (Latin, Sang[uis] Rel[is].) (See GRAAL.)