c.1600, from Fr. contester "dispute, oppose," from M.Fr., from L. contestari (litem) "to call to witness, bring action," from com- "together" + testari "to bear witness," from testis "a witness," (see testament). Calling witnesses as the first step in a legal combat. The noun is 1640s, from the verb. Related: Contestable (1702); contesting (1610s).