Reconstruction:Proto-Slavic/-ъ

Etymology 1
Since mid-19th century two scenarios for the development of Indo-European *-os in Slavic have been proposed, respectively deriving this desinence: A variant of the former view first proposed by Zaliznyak, Dybo and Nikolayev holds that IE *-os became *-ə in Slavic, which developed into *-ъ in mainstream dialects but into in Old Novgorodian. In the latter view, the Old Novgorodian ending can be considered original, with generalisation of the front variant from the soft declension.
 * immediately from with narrowing of the vowel in the final syllable.
 * from the accusative, analogically after other stem classes (u- and i-stems), probably to avoid homonymy with the neuter ending.

Some authors also speculated that *-os could have had both outcomes depending on some other factors, with subsequent generalisation of one or the other in different grammatical categories.

Usage notes

 * Usually verbs ending in -V- change: i→oj, u/y→ov/av (for a/ě see /, )

Related terms

 * (argued to be the "real" reflex of PIE )

Descendants

 * East Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:

Etymology 2
Widely agreed to have been inherited from, itself composed from the thematic vowel and the accusative singular ending. A small minority of researches instead argued for an extension of the u-stem ending.

Descendants

 * East Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:

Etymology 3
From, itself composed from the final vowel of the stem and the nominative singular ending.

Descendants

 * East Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:

Etymology 4
From *-um, itself composed from the final vowel of the stem and the accusative singular ending.

Descendants

 * East Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:

Etymology 5
Two sources have been proposed, depending on the reconstruction of the Indo-European ending: Proponents of the former view have sometimes connected the neocircumflex intonation in Slovene, the stem short vowel in Czech and the Serbo-Croatian desinence with the alleged Proto-Slavic length.
 * or with some kind of shortening.
 * , the supposed athematic genitive plural alongside thematic *-ōm < *-o-om. A variant of this view holds that also thematic stems had *-om without the thematic vowel in Proto-Indo-European.

Descendants

 * East Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic:
 * South Slavic: