W.R. Hardie (1862-1916), "Aims and Methods of Classical Study," Lectures on Classical Subjects
(London: Macmillan and Co., Limited, 1903), pp. 309-336 (at 318-319):
How much knowledge is necessary to enable us to understand the simple phrase, 'the goddess,' in the various contexts where it occurs! In the mouth of an Athenian, ἡ θεός generally means the protectress of Athens, Pallas. At the beginning of Plato's Republic, however, ἡ θεός means the Thracian Bendis, and in Theocritus ἁ θεός is Hecate. The dual again, τὼ θεώ, meant at Athens the great goddesses of Eleusis, Demeter and Persephone. At Sparta, τὼ σιώ meant the Dioscuri, Castor and Pollux: in Boeotia, Amphion and Zethus, the founders of Thebes. When Catullus addresses a goddess as 'Rhamnusia virgo,' we require to know that Nemesis or Adrasteia had a sanctuary at Rhamnus on the coast of Attica.