Theisoa may refer to:

• Theisoa (nymph), one of the nymphs in Greek mythology
• Theisoa (moth), a genus of the moth family Gelechiidae
• Theisoa, Greece, a village in the municipal unit of Andritsaina, Elis, Greece
• Theisoa (Arcadia), a town of ancient Arcadia, Greece
• Theisoa (Orchomenus), a town of ancient Arcadia, Greece

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