Szemerényi's law () is both a sound change and a synchronic phonological rule that operated during an early stage of the Proto-Indo-European language (PIE). Though its effects are evident in many reconstructed as well as attested forms, it did not operate in late PIE, having become morphologized (with exceptions reconstructible via the comparative method). It is named for Hungarian-British linguist Oswald Szemerényi.
Overview The rule deleted coda fricatives or laryngeals or (cover symbol ), with compensatory lengthening occurring in a word-final position after resonants. In other words:
*/-VRs/, */-VRH/ > *-VːR */-VRH-/ > *-VR- (no examples of s-deletion can be reconstructed for PIE)
Morphological effects The law affected the nominative singular forms of the many masculine and feminine nouns whose stem ended in a resonant:
PIE "father" > (Ancient Greek patḗr, Sanskrit pitā́) PIE "parent" > (Ancient Greek genétōr, Latin ) PIE "earth" > (Ancient Greek khthṓn, Sanskrit kṣa, Hittite te-e-kán) The rule also affected the nominative-accusative forms of neuter plural/collective nouns, which ended in : PIE "seeds" > > (on n-deletion see below) Also in the third-person plural perfect ending: PIE (the third-person plural perfect ending) > (Latin , Hittite )
Compare: PIE "word" > (Latin )
Further effects According to another synchronic PIE phonological rule, word-final *n was deleted after *ō, usually by the operation of Szemerényi's law: PIE "dog" > > (Sanskrit , Old Irish )
The PIE reconstruction for "heart" is the single instance where is deleted after , with compensatory lengthening of the preceding vowel. It is not clear whether that is an isolated example or a part of a broader process. PIE "heart" > (Ancient Greek , Hittite )
Exceptions
Some cases were apparently not affected by Szemerényi's law: The accusative plural of thematic nominals. The genitive singular of stems ending in sonorants, such as "of the house" (fossilised in the phrase "master of the house"). Secondary 2nd person singular verb ending with verbs ending in sonorants, such as (from the root "to step, to come").
Morphologization
In PIE, the resulting long vowels had already begun to spread analogically to other nominative singular forms that were not phonologically justified by the law (PIE 'foot'). The word-final sonorants other than were sometimes dropped as well, which demonstrates that this law was already morphologized in the period of "PIE proper", and the long vowel produced was no longer synchronically viewed as the outcome of a process of fricative deletion. Exceptions to Szemerényi's law are found in word-final: PIE "woman" > (Old Irish ) but also (Sanskrit ) as well as medial positions: PIE > Sanskrit , PIE > Sanskrit
The forms without a laryngeal are considered to be more archaic and were likely to have been lexicalized at a later stage of PIE.
See also Glossary of sound laws in the Indo-European languages Stang's law
References