The god's name in the nominative is Ζεύς Zeús /zdeús/. It is inflected as follows: vocative: Ζεῦ / Zeû; accusative: Δία / Día; genitive: Διός / Diós; dative: Διί / Dií.
The name Zeus is the Greek continuation of *Di̯ēus, the Proto-Indo-European god of the daytime sky, also called *Dyeus ph2tēr ("Sky Father"). The god is known under this name in the Rigveda (Vedic Sanskrit Dyaus/Dyaus Pita), Latin (compare Jupiter, from Iuppiter, deriving from the Proto-Indo-European vocative *dyeu-ph2tēr), deriving from the root *dyeu- ("to shine", and in its many derivatives, "sky, heaven, god"). Zeus is the only deity in the Olympic pantheon whose name has such a transparent Indo-European etymology.
The earliest attested forms of the name are the Mycenaean Greek di-we and di-wo, written in Linear b syllabic script.
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