The origin of the Proto-Indo-European nominal plural ending *-ōs

Abstract

Under the view that Proto-Indo-European (PIE) formed its nominal plural forms by adding the plural marker *-s to the case suffix, the ‘expected’ nom.pl. ending in thematic stems would be *-oss, in which the plural marker *-s is added to the nom.sg. ending *-os. By Szemerényi’s law, such an original ending *-oss would give *-ōs with simplification of the final *-ss and lengthening of the preceding vowel. Since the postulated development of *-oss to *-ōs matches the ending *-ōs reconstructed for PIE, it is hypothesized in this paper that the scenario sketched above reflects the actual origin of this reconstructed ending.