Winter's law, named after Werner Winter
, who postulated it in 1978, is a proposed sound law
operating on Balto-Slavic
*/e/, */o/, */a/ (< PIE
*h₂e), */i/ and */u/ according to which they lengthen before unaspirated voiced stops, and that syllable gains rising, acute accent.
*sed- "to sit" (which also gave Latin ''sedeō
'', Sanskrit ''sīdati
'', Ancient Greek ''hézomai
'' and English ''sit
'') > Proto-Balto-Slavic *sēstej (*sēd-tej) > Lithuanian ''sė́sti'', OCS
'' (with regular *dt > *st dissimilation; OCS and Common Slavic yat
/ě/ is a regular reflex of PIE/PBSl. */ē/).
* PIE *h₂ebl- "apple" (that also gave English ''apple
'') > Proto-Balto-Slavic *ābl- > standard Lithuanian ''obuolỹs
'' (accusative ''óbuolį'') and also dialectal forms of ''óbuolas'' and Samogitian
''óbulas'', OCS ''ablъko
'', modern Serbo-Croatian ''jȁbuka
'', Slovene ''jábolko
Winter's law is supposed to show the difference between the reflexes of PIE */b/, */d/, */g/, */gʷ/ in Balto-Slavic (in front of which Winter's law operates in closed syllable) and PIE */bʰ/, */dʰ/, */gʰ/, */gʷʰ/ (before which there is no effect of Winter's law). That shows that in relative chronology, Winter's law operated before PIE aspirated stops */bʰ/, */dʰ/, */gʰ/ merged with PIE plain voiced stops */b/, */d/, */g/ in Balto-Slavic.
Secondarily, Winter's law is also supposed to show the difference between the reflexes of PIE *h₂e > */a/ and PIE */o/ which otherwise merged to */a/ in Balto-Slavic. When those vowels lengthen in accordance with Winter's law, old */a/ (< PIE *h₂e) has lengthened into Balto-Slavic */ā/ (which later gave Lithuanian /o/, Latvian /ā/, OCS /a/), and old */o/ has lengthened into Balto-Slavic */ō/ (which later gave Lithuanian and Latvian ''uo'', but OCS /a/). In later development, which represented Common Slavic innovation, the reflexes of Balto-Slavic */ā/ and */ō/ were merged, and they both result in OCS /a/. This also shows that Winter's law operated prior to the common Balto-Slavic change */o/ > */a/.
The original formulation of Winter's law stated that the vowels regularly lengthened in front of PIE voiced stops in all environments. As much as there were numerous examples that supported this formulation, there were also many counterexamples, such as OCS ''stogъ'' "stack" < PIE *stógos, OCS ''voda
'' "water" < PIE * (collective noun formed from PIE *). An adjustment of Winter's law, with the conclusion that it operates only on closed syllables, was proposed by Matasović
in 1994. Matasović's revision of Winter's law has been used in the Lexikon der indogermanischen Verben
. Other variations of the blocking mechanism for Winter's law have been proposed by Kortlandt
, Shintani, Rasmussen
Not all specialists in Balto-Slavic historical linguistics accept Winter's law. A study of counterexamples led Patri (2006) to conclude that there is no law at all. According to him, exceptions to the law create a too heterogeneous and voluminous set of data to allow any phonological generalization.
* Lachmann's law
, a similar law occurring in Latin