Disputed. Dialectal variants point to Proto-Hellenic *wiskʰū́s, but since the Mycenaean Greek cognate 𐀂𐀱𐀓𐀺𐀈𐀵 (i-su-ku-wo-do-to) lacks the initial /w/, it may have arisen by analogy with *ϝῑ́ς (*wī́s, “power”) (> ἴς (ís)). Early hypotheses assume a relation to Sanskrit विषहते (viṣahate, “to hold fast, endure, withstand, conquer”), from Proto-Indo-European *wi- + *seǵʰ- (“to hold, have power”) (see ἔχω (ékhō)), or alternatively from the same root via a reduplicated u-stem *si-sǵʰ-ús (cf. ἴσχω (ískhō)). Unconvinced by these etymologies, Beekes suggests Pre-Greek substrate origin.
According to Gamkrelidze & Ivanov, a Kartvelian borrowing, compare Proto-Georgian-Zan *s₁xu- (“fat, stout”).
ῐ̓σχῡ́ς • (iskhū́s) f (genitive ῐ̓σχῠ́ος); third declension
| Case / # | Singular | Dual | Plural | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominative | ἡ ῐ̓σχῡ́ς hē iskhū́s |
τὼ ῐ̓σχῠ́ε tṑ iskhúe |
αἱ ῐ̓σχῠ́ες hai iskhúes | ||||||||||
| Genitive | τῆς ῐ̓σχῠ́ος tês iskhúos |
τοῖν ῐ̓σχῠ́οιν toîn iskhúoin |
τῶν ῐ̓σχῠ́ων tôn iskhúōn | ||||||||||
| Dative | τῇ ῐ̓σχῠ́ῐ̈ têi iskhúï |
τοῖν ῐ̓σχῠ́οιν toîn iskhúoin |
ταῖς ῐ̓σχῠ́σῐ / ῐ̓σχῠ́σῐν taîs iskhúsi(n) | ||||||||||
| Accusative | τὴν ῐ̓σχῡ́ν tḕn iskhū́n |
τὼ ῐ̓σχῠ́ε tṑ iskhúe |
τᾱ̀ς ῐ̓σχῦς / ῐ̓σχῠ́ᾰς tā̀s iskhûs / iskhúas | ||||||||||
| Vocative | ῐ̓σχῡ́ iskhū́ |
ῐ̓σχῠ́ε iskhúe |
ῐ̓σχῠ́ες iskhúes | ||||||||||
| Notes: |
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