THEI´SOA(Θεισόα: Eth. Θεισοάτης).
1. A town of Arcadia, in the district Cynuria or Parrhasia, on the northern slope of Mt. Lycaeus, called after the nymph Theisoa, one of the nurses of Zeus. Its inhabitants were removed to Megalopolis upon the foundation of the latter city. Leake places it at the castle of St. Helenabove Lavdha. Ross discovered some ancient remains N. of Andritzäna, which he conjectures may be those of Theisoa. (Paus. 8.38. § § 3, 9, 8.27.4; Steph. B. s. v.;Leake, More, vol. 2. p. 315, Peloponnesiaca, p. 154; Ross, Reisen im Peloponnes, vol. 1. p. 101; Boblaye, Recherches, p. 151.)
2. A town of Arcadia, in the territory of Orchomenus, the inhabitants of which also removed to Megalopolis. It is mentioned along with Methydrium and Teuthis as belonging to the confederation (συντέλεια) of Orchomenos. It is probably represented by the ruins near Dimitzana. (Paus. 8.27. § § 4, 7, 8.28.3; Ross, p. 115.)