Σῖναι

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Names of China

Uncertain, but possibly from Arabic صِين (Ṣīn, “China”) + -αι (-ai), from Middle Persian 𐭰𐭩𐭭 (čīn, “China”), from Sanskrit चीन (Cīna, “China”), and usually held to derive from Old Chinese 秦 (*zin, “Qin”).

Σῖναι • (Sînai) m pl (genitive Σῑνῶν); first declension

(culture) a people of East Asia usually identified as the southern Chinese: the Cantonese, Vietnamese, and other Yue peoples reached via the maritime Silk Road to Panyu (Guangzhou), not known at the time to be related to the Seres reached by the overland route to Chang'an (Xi'an)
- 1878, Franz Delitzsch with Neumann, translated by Thomas Rawson Birks, Commentary on the Book of Isaiah‎ (in English), page 247:
  The name Θῖναι, Strabo, Σῖναι, Ptol., Τζίνιτζα, Kosmas, did not obtain currency first from the founder of the dynasty Tsin; but, long before this, Tsin was the name of a feudal kingdom in Shensi, one of the western provinces of the Sinese land, and Feitsa, the first feudal King of Tsin, began to reign as early as b.c. 897.
  The name Thînai, Strabo, Sînai, Ptol., Tzínitza, Kosmas, did not obtain currency first from the founder of the dynasty Tsin; but, long before this, Tsin was the name of a feudal kingdom in Shensi, one of the western provinces of the Sinese land, and Feitsa, the first feudal King of Tsin, began to reign as early as b.c. 897.
their homeland in southern China: Guangdong and northern Vietnam
their chief city

More information Case / #, Plural ...

Case / #	Plural
Nominative	αἱ Σῖναι hai Sînai
Genitive	τῶν Σῑνῶν tôn Sīnôn
Dative	ταῖς Σῑ́ναις taîs Sī́nais
Accusative	τᾱ̀ς Σῑ́νᾱς tā̀s Sī́nās
Vocative	Σῖναι Sînai
Notes:	This table gives Attic inflectional endings. For declension in other dialects, see Appendix:Ancient Greek dialectal declension.

Ancient Greek