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Webster 1913 Edition
Labarum
‖
Lab′a-rum
,Noun.
pl.
Labara
(#)
. [L.]
The standard adopted by the Emperor Constantine after his conversion to Christianity. It is described as a pike bearing a silk banner hanging from a crosspiece, and surmounted by a golden crown. It bore a monogram of the first two letters (ΧΡ) (which appear like the English letters X and P), of the name of Christ in its Greek form. Later, the name was given to various modifications of this standard.