Szemerényi's law

Szemerényi's law (or Szemerényi's lengthening) is a Proto-Indo-European phonological rule, named after Hungarian linguist Oswald Szemerényi, according to which word-final clusters of vowels (V), resonants (R) and of either */s/ or */h₂/ are simplified by dropping the word-final fricative (*PIE|/h₂/ was phonetically itself probably a back fricative), with compensatory lengthening of the preceding vowel.

This law affected numerous nominative singulars of masculine and feminine nouns, as well as the nominoaccusatives of neuter collectives in *PIE|-h₂

Compare:
* PIE PIE|*ph₂tér-s 'father' > PIE| > Ancient Greek "", Sanskrit "pitā́"

After aplplying the law, the resulting word-final *-n would then be dropped, at least if the preceding segment was (unaccented) *ō. The resulting long vowels had already begun in PIE to spread analogically to other nominative singular forms in which they were not phonologically justified by the law (e.g. PIE PIE| 'foot'), and word-final sonorants other than *-n were sometimes dropped, which demonstrates that this law was already morphologized in the period of "PIE proper".

ee also

* Stang's law

References

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