Monophthongization of diphthongs in Proto-Slavic

Monophthongization of diphthongsis aProto-Slavicsound changein whichdiphthongsturn intovowels.It is one of the key events in the chronology of the Proto-Slavic language. Themonophthongizationof diphthongs restructured the Proto-Slavic language with a strong influence on itsmorphophonology.

The change

Proto-Balto-Slavic,the ancestor of Proto-Slavic, possessed three vocalic diphthongs:*ai,*auand*ei.In Proto-Slavic, these were monophthongized as follows, with the subscript indicating whether the vowels trigger thefirst palatalizationor thesecond.

• *ai > *ě₂, *i₂ - Early Slavic *snaigu > *sněgъ > Serbo-Croatian snijeg
• *au > *u - Early Slavic *saušu > *suxъ > Serbo-Croatian suh
• *ei > *i₁ - Early Slavic *kreivu > *krivъ > Serbo-Croatian kriv

The fourth Proto-Indo-European vocalic diphthong,*eu,had already become*jauin Proto-Balto-Slavic. It then developed into*juin Proto-Slavic, following the same development as for*au.The unrounding of older long*ūto Slavic*yhad already taken place by the time of the monophthongization; the new*ufilled the gap left by it. The first palatalization had also taken place, as the new vowels denoted as*ě₂and*i₂did not trigger it.

While most cases of older*aideveloped into*ě₂,some inflectional endings appear to have developed*i₂instead. It is unclear what factors are involved in triggering one reflex versus the other.

• The o-stem nominative plural (Old Church Slavonicčlověkъ,člověci), reflecting the original Proto-Indo-European pronominal ending*-oy,also seen in Lithuanian-ai.
• The thematic imperative infix (Old Church Slavonicrešti,rekǫ,reci), reflecting the original Proto-Indo-European infix*-oyh₁-.

Dating

Yuri Vladimirovich Shevelevdates the monophthongization of diphthongs to the 5th – 7th century AD.Zdzisław Stieberdates the monophthongization of diphthongs to the 5th or 6th century AD.

Toponymy data

By the time theSlavic migrationto theBalkansbegan, the monophthongization of diphthongs had not yet taken place, as evidenced by the borrowing of theLatinnamePoetovioas the SlavicPtuj.

Subsequent toponyms show the borrowing of the Latin [au] as [ov], which indicates the completion of the process of monophthongization of diphthongs by the time these names were borrowed, for example:

• Latin Lauretum > Serbo-CroatianLovret
• Latin Lauriana > Serbo-CroatianLovran
• Latin Tauriana > Serbo-CroatianTovrljane
• Latin (Lapides) lausiae > Serbo-CroatianLavsa/ Lavca

Bibliography

• Yuri Vladimirovich Shevelev,A Prehistory of Slavic, Heidelberg: Carl Winter Universitätsverlag, 1964.
• Zdzisław Stieber,Zarys gramatyki porównawczej języków słowiańskich, Warszawa: Państwowe Wydawnictwo Naukowe, 2005.ISBN83-01-14542-0