The Greek word Ζεύς
Word Ζεύς
z e.w ς
Meaning Zeus
See also Homeric Greek: Δεύς ‘Zeus’
Homeric Greek: Δίη ‘heavenly’
Linear B: di-wo ‘Zeus’
Linear B: di-we ‘Zeus’
Cypriot Syllabic Script: ti-wo ‘Zeus’
Proto-Indo-European: *dei- ‘to shine, to be bright’
Proto-Indo-European: *dyḗusphatḗr ‘sky-father’

Comments

The supreme god of the Greeks and Romans. The earliest attested forms di-wo and di-we are found in Mycenaean Linear B documents.

The name derives from the Proto-Indo-European root *dieu-/*dyeu- 'sky, heaven' (→ 'god') which is preserved in many languages apart from Greek and Italic: Skt. dyauh '(god of) heaven, day' , Hittite šiú-, šiúna- 'god', Palaic tiuna 'god', Lydian ciw- etc. The root in turn has been suggested to derive from PIE *dei- 'shine'. Other old correspondences are Ζεῡ πάτερ, Δειπάτυρος = Lat. Jupiter, Zῆν = Skt. dyam, Lat. diem (whence a new nom. diēs, Diēspiter) which allow a reconstruction of a PIE supreme god *dyḗusphatḗr.

Case declension

Nominative Ζεὺς
Genetive Δι(ϝ)ὸς
Dative  Δι(ϝ)ὶ
Accusative  Δία
Vocative Ζεῦ

References

Beekes, Robert. Etymological dictionary of Greek. Brill, 2010
Mallory, James P., and Douglas Q. Adams. The oxford introduction to proto-indo-european and the proto-indo-european world. Oxford University Press, 2006.