This Proto-Slavic entry contains reconstructed terms and roots. As such, the term(s) in this entry are not directly attested, but are hypothesized to have existed based on comparative evidence.

From Proto-Balto-Slavic *swajas, from Proto-Indo-European *swoyos from *swé. Cognate with Old Prussian swais, Lithuanian savas, Latvian savs, Latgalian sovs, Latin suus, German sein, Old Norse sik (“oneself”), Gothic 𐍃𐍅𐌴𐍃 (swēs, “one's own”), Sanskrit स्व (sva, “one's own”).

*svojь

1. one's own (his, her, its, their own)

• *svobь
  • *svobodà (“freedom”)
• *svojakъ (“relative, cousin”)
• *svojatъ (“intrinsic to oneself”)
• *svojьtьba (“family, kin, relatives”)

• East Slavic:
  • Old East Slavic: свои (svoi)
    • Belarusian: свой (svoj)
    • Russian: свой (svoj)
    • Ukrainian: свій (svij)
• South Slavic:
  • Old Church Slavonic: свои (svoi)
  • Bulgarian: свой (svoj)
  • Macedonian: свој (svoj)
  • Serbo-Croatian: svȏj / сво̑ј
  • Slovene: svọ́j (tonal orthography)
• West Slavic:
  • Old Czech: svój
    • Czech: svůj
  • Old Polish: swój
    • Polish: swój
    • Silesian: swōj
  • Slovak: svoj
  • Pomeranian:
    • Kashubian: swój
    • Slovincian: swój
  • Sorbian:
    • Upper Sorbian: swój
    • Lower Sorbian: swój

• Vasmer, Max (1964–1973) “свой”, in Oleg Trubachyov, transl., Этимологический словарь русского языка [Etymological Dictionary of the Russian Language] (in Russian), Moscow: Progress