Lewis & Short

spectātrix, īcis, f. [spectator].

  1. I. She that looks at or observes a thing, Plaut. Merc. 3, 4, 12; 5, 2, 1; Sen. Cons. ad Marc. 18 med.; Ov. Am. 2, 12, 26: scelerum, Luc. 3, 129.
  2. II. She that judges or tries: incorrupta praeteritorum (posteritas), Amm. 30, 8, 1: humanorum, id. 22, 3, 12: spectatrix dijudicatrixque omnium rerum, App. Dogm. Plat. 2, p. 15, 23.