Compurgator
Pronunciation : Com"pur*ga`tor
Part of Speech : n.
Etymology : [LL.]
Definition : Defn: One who bears testimony or swears to the veracity or innocence of another. See Purgation; also Wager of law, under Wager. All they who know me . . . will say they have reason in this matter to be my compurgators. Chillingworth.
Source : Webster's Unabridged Dictionary, 1913