There are five vowel phonemes in Standard Russian. Vowels tend to merge when they are unstressed. The vowels /a/ and /o/ have the same unstressed allophones for a number of dialects and reduce to an unclear schwa. Unstressed /e/ may become more central and merge with /i/. Under some circumstances, /a/, /e/, /i/ and /o/ may all merge. The fifth vowel, /u/, may also be centralized but does not typically merge with any of the other vowels.
Other types of reduction are phonetic, such as that of high vowels (/i/ and /u/), which become near-close so игра́ть ('to play') is pronounced [ɪˈɡratʲ], and мужчи́на ('man') is pronounced [mʊˈɕːinə].
Russian orthography does not reflect vowel reduction, which can confuse foreign-language learners.
The five Russian vowels /u, i, e, a, o/ in unstressed position show two levels of reduction:
- The first degree reduction in the first pretonic position (immediately before the stress).
- The second degree reduction in other than the first pretonic position.
The allophonic result of the reduction is also heavily dependent on the quality of the preceding consonant as well as the lack of it thereof. Thus the reduction is further grouped into three types according to the environment:
- After hard (non-palatalized or velarized) consonants (including always hard /ts/).
- After the hard retroflex sibilants /ʂ/ and /ʐ/.
- After soft (palatalized) consonants (including always soft /tɕ/ and /ɕː/) and semi-vowel /j/.
The unstressed vowels also may be grouped in series, reflecting similar patterns of the reduction:
- High /u/ and /i/ (never reduced).
- Non-high /a/, /e/ and /o/ (always reduced).
- Back /a/ and /o/ (both exhibit akanye).
- Front /i/ and /e/ (both exhibit ikanye).
- Back high /u/ (never reduced).
Two high vowels /u/ and /i/ are usually thought to undergo no reduction. However, on the phonetic level they show allophonic centralization, particularly under the influence of the preceding or the following consonants. The unstressed high back vowel /u/ is either [ʊ] (after hard consonants, written ⟨у⟩) or [ʊ̈] (after soft consonants, written ⟨ю⟩, except ⟨чу⟩, ⟨щу⟩). The unstressed high front vowel /i/ is either [i] or [ɪ] (after soft consonants, written ⟨и⟩), or [ɨ] or [ɪ̈] (after hard consonants, written ⟨ы⟩, except ⟨ши⟩, ⟨жи⟩). Nevertheless, in rapid colloquial speech they both may be reduced to schwa [ə], for example, до́брым [ˈdobrɨ̆m] ('kind', instrumental case, singular masculine-neuter) versus до́бром [ˈdobrəm] ('kind', prepositional case, sg. masc.-neut.): the case ending //-im// in the former may surface as [-əm] like the case ending //-om//, thus leading to the merger of /i/ and /o/; or де́лают [ˈdʲeləjʊ̈t] ('they do') versus де́лает [ˈdʲeləjɪt] ('he/it does'): both may surface as [ˈdʲeləɪt] or [ˈdʲeləːt].
Other than in Northern Russian dialects Russian speakers have a strong tendency to merge unstressed /a/ and /o/, called akanye (аканье). It contrasts with okanye (оканье) pronunciations. It works in Standard Russian as follows:
- After hard (non-palatalised) consonants, standard phonological rules prescribe a two-level reduction. The stressed vowel is normally the longest and the only place (with certain exceptions) that the sound [o] is permitted. In the syllable immediately before the stress and in absolute word-initial position, both reduce to [ɐ] (sometimes also transcribed as [ʌ]). In all other locations, /a/ and /o/ are reduced further to a short [ə]. For example, паро́м [pɐˈrom] ('ferry'), о́блако [ˈobləkə] ('cloud'), трава́ [trɐˈva] ('grass'). In practice, the second reduction has a gradient character: if the vowel in question is pronounced for enough time (such as by hyperarticulation), it may be pronounced as [ɐ]. Shorter durations have the effect of gradually transforming [ɐ] into schwa. It has been argued recently that the change of sound quality during second-degree reduction is merely an artifact of duration-dependent "phonetic undershoot", when the speaker intends to pronounce [ɐ], but the limited time reduces the likelihood of the tongue being able to arrive at the intended vowel target.
- In fast speech, reduction ultimately may result in the vowel being dropped altogether, with the preceding consonant slightly lengthened or turned into a syllabic consonant: сапоги́ [sːpɐˈɡʲi], vs. [səpɐˈɡʲi] ('boots'), потоло́к [pːtɐˈlok] ('ceiling'), де́сять [ˈdʲesʲtʲ] ('ten').
- When ⟨аа⟩, ⟨ао⟩, ⟨оа⟩, or ⟨оо⟩ is written in a word, it indicates [ɐ.ɐ] so сообража́ть ('to realise') is pronounced [sɐ.ɐ.brɐˈʐatʲ].
- In prepositions, the processes occur even across word boundaries, as in под мо́рем [pɐˈd‿morʲɪm] ('under the sea'), на оборо́те [nɐ.ɐbɐˈrotʲɪ] ('on the reverse side', 'overleaf'). It does not occur for other parts of speech.
- Both /o/ and /a/ merge with /i/ after palatalised consonants and /j/ (/o/ is written as ⟨е⟩ in those positions[example needed]). This merger also occurs for /o/ after retroflex consonants. Examples: жена́ /ʐiˈna/ (phonetically [ʐɨ̞ˈna]; 'wife'), язы́к /jiˈzik/ (phonetically [jɪˈzɨk]; 'tongue').
Across certain word-final suffixes, the reductions do not completely apply. In certain suffixes, after palatalised consonants and /j/, /a/ and /o/ (which is written as ⟨е⟩) can be distinguished from /i/ and from each other: по́ле [ˈpolʲɪ] ('field' nominative singular neuter) is different from по́ля [ˈpolʲə] ('field' singular genitive), and the final sounds differ from the realisation of /i/ in that position.
There are a number of exceptions to the above comments regarding the akanye:
- /o/ is not always reduced in foreign borrowings: [ˈradʲɪ.o] ('radio'). The common pattern for this exception is the final unstressed о being preceded by another vowel (Анто́нио, кака́о, сте́рео). Compare with мо́но, фо́то whose final unstressed о is reduced to [ə].
- Speakers with old-Moscovian reflexes pronounce /a/ as /ɨ/ after retroflex consonants /ʐ/ and /ʂ/ (thereby mimicking the reduction of /o/); that pronunciation generally applies only to жале́ть [ʐɨˈlʲetʲ] ('to regret'), к сожале́нию [ksəʐɨˈlʲenʲɪju] ('unfortunately'), and oblique cases of ло́шадь [ˈloʂətʲ] ('horse'), such as лошаде́й [lə.ʂɨˈdʲej].
- /ɨ/ replaces /a/ after /t͡s/ in the oblique cases of some numerals: два́дцать [ˈdvat͡sɨtʲ] ('twenty').
The main feature of front vowel reduction is ikanye (иканье), the merger of unstressed /e/ with /i/. Because /i/ has several allophones (depending on both stress and proximity to palatalised consonants), unstressed /e/ is pronounced as one of these allophones and not actually as the close front unrounded vowel. For example, семена́ /sʲimʲiˈna/ ('seeds') is pronounced [sʲɪmʲɪˈna], цена́ /t͡siˈna/ ('price') [t͡sɨ̞ˈna].
In registers without the merger (yekanye or еканье), unstressed /e/ is more retracted. Even then, however, the distinction between unstressed /e/ and unstressed /i/ is most clearly heard in the syllable just before the stress. Thus, прида́ть ('to add to') contrasts with преда́ть ('to betray'). The two are pronounced [prʲɪˈdatʲ] and [prʲe̠ˈdatʲ] respectively. Yekanye pronunciation is coupled with a stronger tendency for both unstressed /a/ and /o/ to be pronounced the same as /i/.
Speakers may switch between the two types of pronunciation because of various factors, the most important factor likely being speed of pronunciation.
Yakanye (яканье) is the pronunciation of unstressed /e/ and /a/ following palatalised consonants preceding a stressed syllable as /a/ rather than /i/ (несли́ is pronounced [nʲasˈlʲi], not [nʲɪsˈlʲi]).
Orthography Standard pronunciation Yakanye pronunciation Translation А у нас в Ряза́ни [ə‿ʊ‿ˈnas v‿rʲɪˈzanʲɪ] [a w nəs wrʲaˈzanʲə] And we have in Ryazan пироги́ с глаза́ми. [pʲɪrɐˈɡʲɪ z‿ɡlɐˈzamʲɪ] [pʲɪˈraɣʲɪ z ɣlaˈzamʲə] Pies with eyes: Их едя́т, [ɪx jɪˈdʲat] [ɪxʲ jaˈdʲætʲ] While being eaten, а они́ глядя́т. [ɐ‿ɐˈnʲi ɡlʲɪˈdʲat] [ə aˈnʲi ɣlʲaˈdʲætʲ] They stare at you.
The example also demonstrates other features of Southern dialects: palatalised final /tʲ/ in the 3rd person forms of verbs, [ɣ] instead of [ɡ] and [w] instead of [u] (in some places) and [v], clear unstressed [a] in place of [ɐ] or [ə].
Vowel reduction makes some words have spellings that contradict their etymology, such as паро́м (instead of поро́м, which was standard spelling before the Ushakov Dictionary), карава́й (instead of корова́й, the standard spelling until the reform of 1956), свидетель (instead of сведетель, with a long history).
In the closely related Belarusian language, original /o/ has merged with /a/ as in Standard Russian, but the reduced pronunciation is reflected in the spelling.
- Barnes, Jonathan (2007), Phonetics and Phonology in Russian Unstressed Vowel Reduction: A Study in Hyperarticulation (PDF), Boston, MA
- Crosswhite, Katherine Margaret (2000), "Vowel Reduction in Russian: A Unified Account of Standard, Dialectal, and 'Dissimilative' Patterns" (PDF), University of Rochester Working Papers in the Language Sciences, 1 (1): 107–172
- Halle, Morris (1959), Sound Pattern of Russian, MIT Press
- Iosad, Pavel (2012), "Vowel reduction in Russian: no phonetics in phonology", Journal of Linguistics, 48 (3): 521–527, doi:10.1017/S0022226712000102
- Jones, Daniel; Ward, Dennis (1969), The Phonetics of Russian, Cambridge University Press
- Padgett, Jaye; Tabain, Marija (2005), "Adaptive Dispersion Theory and Phonological Vowel Reduction in Russian" (PDF), Phonetica, 62 (1): 14–54, doi:10.1159/000087223, PMID 16116302
- Timberlake, Alan (2004), A Reference Grammar of Russian, Cambridge University Press, ISBN 9781139449342
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- Barnes, Jonathan (January 11, 2004), Vowel Reduction in Russian: The Categorical and the Gradient (PDF), Boston, MA
- The Language of the Russian Village (A dialect atlas for use in Russian junior high school. Maps 12 and 13 shows the extent of vowel reduction in Russian dialects.) (in Russian)