Probably from Σάρδεις (Sárdeis, “Sardis”) + -ιον (-ion, diminutive suffix), because it was its place of origin.
σᾰ́ρδῐον • (sárdion) n (genitive σᾰρδῐ́ου); second declension
| Case / # | Singular | Dual | Plural | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominative | τὸ σᾰ́ρδῐον tò sárdion |
τὼ σᾰρδῐ́ω tṑ sardíō |
τᾰ̀ σᾰ́ρδῐᾰ tà sárdia | ||||||||||
| Genitive | τοῦ σᾰρδῐ́ου toû sardíou |
τοῖν σᾰρδῐ́οιν toîn sardíoin |
τῶν σᾰρδῐ́ων tôn sardíōn | ||||||||||
| Dative | τῷ σᾰρδῐ́ῳ tôi sardíōi |
τοῖν σᾰρδῐ́οιν toîn sardíoin |
τοῖς σᾰρδῐ́οις toîs sardíois | ||||||||||
| Accusative | τὸ σᾰ́ρδῐον tò sárdion |
τὼ σᾰρδῐ́ω tṑ sardíō |
τᾰ̀ σᾰ́ρδῐᾰ tà sárdia | ||||||||||
| Vocative | σᾰ́ρδῐον sárdion |
σᾰρδῐ́ω sardíō |
σᾰ́ρδῐᾰ sárdia | ||||||||||
| Notes: |
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