Probably from Σάρδεις (Sárdeis, “Sardis”) + -ιον (-ion, diminutive suffix), because it was its place of origin.
σᾰ́ρδῐον • (sắrdĭon) n (genitive σᾰρδῐ́ου); second declension
| Case / # | Singular | Dual | Plural | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominative | τὸ σᾰ́ρδῐον tò sắrdĭon |
τὼ σᾰρδῐ́ω tṑ sărdĭ́ō |
τᾰ̀ σᾰ́ρδῐᾰ tằ sắrdĭă | ||||||||||
| Genitive | τοῦ σᾰρδῐ́ου toû sărdĭ́ou |
τοῖν σᾰρδῐ́οιν toîn sărdĭ́oin |
τῶν σᾰρδῐ́ων tôn sărdĭ́ōn | ||||||||||
| Dative | τῷ σᾰρδῐ́ῳ tôi sărdĭ́ōi |
τοῖν σᾰρδῐ́οιν toîn sărdĭ́oin |
τοῖς σᾰρδῐ́οις toîs sărdĭ́ois | ||||||||||
| Accusative | τὸ σᾰ́ρδῐον tò sắrdĭon |
τὼ σᾰρδῐ́ω tṑ sărdĭ́ō |
τᾰ̀ σᾰ́ρδῐᾰ tằ sắrdĭă | ||||||||||
| Vocative | σᾰ́ρδῐον sắrdĭon |
σᾰρδῐ́ω sărdĭ́ō |
σᾰ́ρδῐᾰ sắrdĭă | ||||||||||
| Notes: |
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