What is "wager of law"

Compurgation \Com`pur*ga"tion\, n. [L. compurgatio, fr. compurgare to purify wholly; com- + purgare to make pure. See Purge, v. t.]

1. (Law) The act or practice of justifying or confirming a man's veracity by the oath of others; -- called also wager of law. See Purgation; also Wager of law, under Wager.

2. Exculpation by testimony to one's veracity or innocence.

   He was privileged from his childhood from suspicion of incontinency and needed no compurgation.
   --Bp. Hacket.

n. (context legal historical English) The giving of gage, or surety, by a defendant in an action of debt, that at a certain day assigned he would take an oath in open court that he did not owe the debt, and at the same time bring with him eleven compurgators who would avow that they believed in their consciences that he spoke the truth.