{{Short description|Proto-Indo-European sound law}} {{DISPLAYTITLE:''ruki'' sound law}} {{More citations needed|date=August 2007}} The '''{{translit|ru|ruki}} sound law''', also known as the '''{{translit|ru|ruki}} rule''' or '''''iurk'' rule''', is a historical sound change that took place in the satem branches of the Indo-European language family, namely in Balto-Slavic, Armenian,<ref>{{citation|last=Mayer|first=Harvey E.|title=Baltic Membership in the West Satem Group|journal=Journal of Baltic Studies|year=1980|volume=11|issue=4|pages=356–366|doi=10.1080/01629778000000351}}</ref> and Indo-Iranian. According to this sound law, an original {{lang|ine-x-proto|s}} changed to {{lang|ine-x-proto|š}} (a sound similar to English ⟨sh⟩) after the consonants {{lang|ine-x-proto|r}}, {{lang|ine-x-proto|k}}, {{lang|ine-x-proto|g}}, {{lang|ine-x-proto|gʰ}} and the semi-vowels {{lang|ine-x-proto|w}} (*u̯) and {{lang|ine-x-proto|y}} (*i̯), as well as the syllabic allophones {{lang|ine-x-proto|r̥}}, {{lang|ine-x-proto|i}}, and {{lang|ine-x-proto|u}}:
: {{lang|ine-x-proto|s}} > {{lang|ine-x-proto|š}} / {{lang|ine-x-proto|proto=no|{*r, *w, *K, *y} }} _
Specifically, the initial stage involves the retraction of the coronal sibilant {{lang|ine-x-proto|s}} after semi-vowels, {{lang|ine-x-proto|r}}, or a velar consonant {{lang|ine-x-proto|k}}, {{lang|ine-x-proto|g}} or {{lang|ine-x-proto|gʰ}}. In the second stage, leveling of the sibilant system resulted in retroflexion (cf. Sanskrit ष {{lang|sa|[ʂ]}} and Proto-Slavic), and later retraction to velar {{lang|ine-x-proto|x}} in Slavic and some Middle Indic languages. This rule was first formulated by Holger Pedersen, and it is sometimes known as ''Pedersen's law'', although this term is also applied to another sound law concerning stress in the Balto-Slavic languages.
The name {{translit|ru|ruki}} comes from the sounds (r, u, K, i) which triggered the sound change. The law is stated as a mnemonic rule because the word {{lang|ru|руки}} ({{translit|ru|ruki}}) means 'hands, arms' in Russian, or is the genitive singular form ('of the hand') of рука (compare ''rule of thumb'').
==Applications to language groups== The rule was originally formulated for Slavic languages. It was later proposed to be valid in some degree for all satem languages, and exceptionless for the Indo-Iranian languages. (There appears to be one exception at least in some Nuristani languages, however.) In Baltic and Albanian, it is limited or affected to a greater or lesser extent by other sound laws. Nevertheless, it has to have been universal in these branches of the IE languages, and the lack of Slavic reflexes before consonants is due rather to their merger with the reflexes of other sibilants.
===Slavic languages=== In Slavic languages the process is regular before a vowel, but it does not take place before consonants. The final result is the voiceless velar fricative {{lang|ine-x-proto|x}}, which is even more retracted than the {{lang|ine-x-proto|š}}. This velar fricative changed back into {{lang|ine-x-proto|š}} before a front vowel or the palatal approximant {{lang|ine-x-proto|y}}.
Examples: * PIE {{lang|ine-x-proto|*h₂sowsós}} > Proto-Balto-Slavic *saušás > Proto-Slavic {{lang|sla-x-proto|*sȗxъ}} "dry" * PIE {{lang|ine-x-proto|*pers-}} "to sprinkle, spatter" > Proto-Balto-Slavic *paršás > Proto-Slavic {{lang|sla-x-proto|*pȏrxъ}} "dust"
===Indo-Iranian languages=== In Indo-Iranian *''r'' and *''l'' merged, and the change worked even after the new sound; e.g. Avestan ''karš-'', Sanskrit {{wikt-lang|sa|कर्षति}} ''kárṣati'' 'to plough' < PIE {{wikt-lang|ine-pro|*kʷels-}}.<ref name="Skjaervo09">{{cite encyclopedia|first=Prods Oktor|last=Skjærvø|title=Old Iranian|encyclopedia=The Iranian Languages|year=2009|publisher=Routledge|page=49}}</ref><ref name="Lubotsky18">{{cite encyclopedia|first=Alexander|last=Lubotsky|title=The phonology of Proto-Indo-Iranian|encyclopedia=Handbook of Comparative and Historical Indo-European Linguistics|year=2018|publisher=de Gruyter|page=1881}}</ref> This has been cited as evidence by many scholars{{who|date=February 2020}} as an argument for the later influence of Iranian languages on Proto-Slavic. There are obvious drawbacks in the theory. First, the two sounds must have been very close (''r'' or ''l''), so that both could have triggered the change in Indo-Iranian. Second, there are no real examples of this change working in Slavic, and it is also doubtful that only this change ({{translit|ru|ruki}}) and no other such change of sibilants (e.g. {{lang|ine-x-proto|s}} > ''h'') was borrowed into Slavic.
The syllabic laryngeal *H̥ becomes *i in Proto-Indo-Iranian, and this also triggered {{translit|ru|ruki}}.<ref>F. B. J. Kuiper. 1976. "Old East Iranian dialects." ''Indo-Iranian Journal'' '''18''', p. 242.</ref><ref name="Lubotsky18"/>
A later extension of {{translit|ru|ruki}} was particular to the Iranian languages: *s, *z shift to *š, *ž also after the labial stops *p, *b, including even secondary *s from Proto-Indo-Iranian *ć < PIE *ḱ.<ref name="Skjaervo09"/><ref>{{cite encyclopedia|first=Alberto|last=Cantera|title=The phonology of Iranian|encyclopedia=Handbook of Comparative and Historical Indo-European Linguistics|year=2018|publisher=de Gruyter|page=25|url=https://www.academia.edu/35284207}}</ref>
====Nuristani==== The {{translit|ru|ruki}} rule also displays a rather different behavior in Nuristani, however recent research on the inherited layer of the Nuristani lexicon has revealed further details on the {{translit|ru|ruki}} law pointing to a different conclusion.<ref name="Halfmann2025">{{cite book|author=Jakob Halfmann|title=The Diversification of Indo-Iranian and the Position of the Nuristani Languages|url=https://medialibrary.reichert-verlag.de/en/9783752003543_the_diversification_of_indo_iranian_and_the_position_of_the_nuristani_languages/|date=25 November 2025|publisher=Reichert Verlag|isbn=978-3-7520-0912-5}}</ref><ref>Hegedűs, Irén. [https://books.google.com/books?id=vm2SugMy8C0C&dq=Proto-Nuristani&pg=PA145 "The RUKI-rule in Nuristani."] The sound of Indo-European: phonetics, phonemics and morphophonemics (Copenhagen studies in Indo-European vol. 4) (2012): 145-168.</ref><ref>{{cite encyclopedia|first=Caley|last=Smith|title=30. The dialectology of Indic|encyclopedia=Handbook of Comparative and Historical Indo-European Linguistics|chapter=The dialectology of Indic|year=2017|pages=417–447|publisher=de Gruyter|doi=10.1515/9783110261288-030|isbn=9783110261288}}</ref>
* The reflex of the Proto-Indo-European sequences ''*tḱ'' and ''*ḱs'' is Proto-Nuristani ''*ċċ'', reflected in all Nuristani languages as ''ċ'' (pronounced [t͡s]), different to that of plain ''*ḱ'' > ''*ċ'' (''ċ'' in most Nuristani languages, ''s'' in Ashkun and ''z'' in Prasun), thus in this context there is no evidence of the operation of {{translit|ru|ruki}}. For example, the word for "bear", reflecting Proto-Indo-European ''*h₂ŕ̥tḱos'' (Sanskrit ''ṛ́k'''ṣ'''a'' "bear", Avestan ''ar'''ṣ̌'''a'') shows a dental affricate in most Nuristani languages, such as Ashkun and Katë ''i'''ċ''''', and Nuristani Kalasha ''o'''ċ''''', but Prasun has ''i'''tr'''u'' with an apparently irregular reflex. * Proto-Indo-European sequences ''*ks'' and ''*kʷs'' appear to have become ''c̣'' in modern Nuristani. Thus Proto-Indo-European ''*ksurós'' "razor" is reflected as ''kṣurá'' in Sanskrit, but ''c̣uři'' "sickle" in the Southeastern Katë dialect. However, this is explained by Halfmann as a sound development found in borrowings from Indo-Aryan (in this case from Indo-Aryan ''kṣurikā''), and is in no way indicative of the inherited reflex, which appears to be a retracted sibilant yielding ''š'' in Katë and Nuristani Kalasha, and ''ṣ'' in Prasun. One example of the inherited reflex is ''*ksen-'' "to card wool" > ''*(wi-)kšan-'' > Northeastern Katë ''višn-'' and Prasun ''-ṣn-''. * Various cases where {{translit|ru|ruki}} failed to operate after ''*i'' and ''*u'' in Nuristani exist. Hegedűs notes that these all seem to trace back to PIE etyma where the ''*us'' and ''*is'' sequences were earlier ''*uHs'' and ''*iHs'', meaning the laryngeals seem to have blocked the operation of {{translit|ru|ruki}}. For example, PIE ''*múh₂s'' "mouse" > Sanskrit ''mū́ṣ'', Avestan ''mūš'', but Northeastern Katë ''musë'', Prasun ''müs'', while Nuristani Kalasha ''pusa'' is of dubious etymology on account of the different initial consonant, and Ashkun ''moṣ'' shows the Indo-Aryan reflex, probably due to borrowing. However, examples such as Proto-Indo-European ''*dowséh₂'' "evening" > Sanskrit ''doṣā́'' show ''s'' in Katë ''dus'' and Prasun ''wulus'', both meaning "yesterday". However, the apparent application of {{translit|ru|ruki}} after ''*i'', such as PIE ''*wisós'' "poison" > Katë ''viš'', also occurs before ''*i'', as in PIE ''*-si'' "second-person singular verbal ending" > Katë ''-š''. This is therefore related to palatalization near ''*i'', which is cross-linguistically common and is therefore separate from the actual {{translit|ru|ruki}} rule. * Proto-Indo-European ''*rs'' and ''*ls'' merge into modern Nuristani ''ṣ'', thus after ''*r'' we do actually see proper {{translit|ru|ruki}}-like behavior in Nuristani, such as Proto-Indo-European ''*kʷels-'' yielding Southeastern Katë ''kṣō-'' "to pull" (< ''*karsā(p/w)aya-''). While this occurs in inherited words, the sound change may be due to later convergence with Indo-Aryan and need not be associated with the {{translit|ru|ruki}} rule, instead being associated with the general tendency of retroflexion.
Halfmann therefore concludes that the apparent lack of {{translit|ru|ruki}} in Nuristani is not an archaism, but more likely the merger of Proto-Indo-Iranian ''*s'' and ''*š'' as ''s'' after the emergence of the retracted sibilant deriving from ''*ks'', with a series of palatalizations occurring after the merger.
===Albanian=== According to Orel (2000: 62),<ref>{{citation|first=Vladimir|last=Orel|title=A Concise Historical Grammar of Proto-Albanian|year=2000|publisher=Brill}}</ref> Albanian shows a limited {{translit|ru|ruki}}-like development, where ''*s'' becomes ''sh'' only after PIE *y, *w (including their vocalic counterparts ''*i, *u''). E.g. * ''le'''sh''''' 'wool, fleece, hair' < *la'''ys'''a, cf. Slavic *listъ 'leaf' < *leys-to- * ''da'''sh''''' 'ram' < *da'''ws'''a, cf. Germanic *deuzą < *dʰews-om * ''pi'''sh'''ë'' 'pine' < *p'''is'''ā, cf. Latin ''pīnus'' 'pine' < *pi(t)snos * ''pru'''sh''''' 'ember' < *pr'''us'''a, cf. Latin ''prūna'' 'ember' < *prusnā; Sanskrit ''ploṣati'' 'to burn' < *prews- This differs from the development of ''*rs'', ''*ks'', and of ''*s'' after other vowels, e.g. * ''dje'''rr''''' 'fallow land' < *de'''rs'''a, cf. Greek ''χέρσος'' 'dry land' < *ǵʰers- * '''''h'''irrë'' 'whey' < *'''ks'''irā, cf. Sanskrit क्षीर / ''kṣīrá'' 'milk' * ''ko'''h'''ë'' 'time' < *k'''ās'''ā, cf. Slavic *časъ 'time' < *kʷeh₁s-eh₂
However, this view of Albanian is controversial. Firstly, the words in question that Orel bases this theory on have shaky etymologies. ''Dash'' has a disputed etymology, with rival versions attributing the word not to Proto-Indo-European *dʰews-om but instead *dʰeh₁-l-,<ref>Aleksandar Loma, Albano-Caucasica Pastoralia, 2006</ref> or *demh₂ from *dmh₂ "to tame".<ref>Demiraj, Bardhyl. (1997). ''Albanische Etymologien''. Amsterdam - Atlanta: Rodopi, 1997. Pp 124-5</ref> ''Pishë'' meanwhile is argued to not be inherited from Proto-Indo-European at all; rather it and its soundalikes in Greek and Latin are in fact substrate vocabulary.<ref>Beekes R. 2010. Etymological dictionary of Greek. [Leiden Indo-European etymological dic-tionary series 10]. Leiden, Boston. Pages 1198-1199.</ref> ''Lesh'' is alternatively attributed instead to *h₂welh₁- "wool", making it cognate to Latin ''vellus''.<ref>Demiraj, Bardhyl (1997). ''Albanische Etymologien''. Amsterdam, Atlanta: Rodopi. Page 238.</ref>
Meanwhile, no {{translit|ru|ruki}}-like rule is included in other studies of Proto-Albanian diachrony. Michiel de Vaan (2015) instead has a Proto-Albanian *ʃ emerging from different means, which barely resemble a {{translit|ru|ruki}} law: Indo-European *ks shares the fate of simple *s in becoming *ʃ before *t (as occurred for ''jashtë'' "outside" and ''gjashtë'' "six", but not other cases with *ks where *t did not follow), with *t as the conditioning factor, rather than the prior *k.<ref name=DeVaan>{{cite book |last1=De Vaan |first1=Michiel |editor1-last=Klein |editor1-first=Jared |editor2-last=Joseph |editor2-first=Brian |editor3-last=Fritz |editor3-first=Matthew |title=Handbook of Comparative and Historical Indo-European Linguistics |date=2015 |publisher=De Gruyter Mouton |pages=1745–1746 |chapter=95. The Phonology of Albanian}}</ref> Meanwhile, the development of *s itself is highly disputed,<ref>Historische Phonologie. In: Stefan Schumacher and Joachim Matzinger. ''Die Verben des Altalbanischen. Belegwörterbuch, Vorgeschichte und Etymologie''. Wiesbaden: Harrassowitz, 205−276. Pages 258-265</ref> but in contrast to Orel's view that it was conditioned on a {{translit|ru|ruki}}-like phenomenon, De Vaan<ref name=DeVaan/> prefers Kortlandt's<ref>Kortlandt, Frederik (1987). Reflexes of Indo-European consonants in Albanian. ''Orpheus 8'' (Georgiev Memorial Volume): 35−37.</ref> view that *s became *ʃ when either followed by an unstressed vowel or intervocalically, regardless of the quality of nearby vowels.
==See also== * Glossary of sound laws in the Indo-European languages
==Notes== {{reflist}}
{{Slavic languages}} {{Proto-Indo-European language}}
Category:Indo-European sound laws Category:Slavic phonological features