The Story of Jers

Jan 11, 2015 by

Let’s start with a puzzle that concerns not OCS directly but modern Russian. Consider the following nominative and genitive forms of nouns; in addition to the suffix –a for the genitive, something else happens here:

kov’or kovr-a ‘carpet’
šat’or šatr-a ‘marquee’
BUT: šof’or šof’or-a (NOT: šofr-a!) ‘chauffeur’
Similarly: ot’ec otc-a ‘father’
d’en’ dn’-a ‘day’
p’en’ pn’-a ‘stump’
l’ev l’v-a ‘lion’
BUT: l’es l’es-a (NOT: l’s-a!) ‘forest’


Why in some words the addition of the genitive suffix –a is accompanied by the loss of the vowel in the previous syllable, but in other words it is not? The answer will come at the end of the post, but first we have to return to Old Church Slavonic.

Csl-luke20Old Church Slavonic (OCS) had two reduced, lax vowels that require special attention—the so-called “jers” (pronounced with the /j/ of ‘you’ followed by “airs”). Spelled in Cyrillic with “ь” and “ъ”, the front and back jers are pronounced similarly to the English /ɪ/ in pit and /ʊ/ in put, respectively. Unlike in modern Russian, these symbols do not denote some qualities of consonants and are always pronounced. In OCS, all syllables were open, that is ending in a vowel. Hence, agnьcь ‘lamb’ has three syllables, with the stress on the first syllable: /’a.gnɪ.tsɪ/. Similarly, the back jer is pronounced at the end of rabъ ‘slave’: /’ra.bʊ/. It is thought that jers were also inserted to break up consonant clusters in loanwords, such as Pavьlъ ‘Paul’ from the Greek Παύλος (pronounced /’pavlos/); cf. Lunt (2001: 34, section 2.53).

Another rule that applied in OCS is the neutralization of contrast between tense and lax high unrounded vowels before /j/. In this position, the front jer alternated with /i/ and the back jer with /y/, the back (or central) high unrounded vowel. (In OCS grammars, including Lunt’s, this vowel is symbolized by “y”; the IPA symbols is /ɨ/; in modern Russian it is spelled as «ы».) As noted in Lunt (2001: 35), “*ljudьje and *ljudije, *novъjь and *novyjь are equivalent; scribes employ alternate spellings like людье and людие, новъи and новыи” (for more details, see Lunt 2001: 35, section 2.61). In our “Life of Constantine” text, we encounter this in абье ‘immediately’, which can be pronounced either as /abɪje/ or /abije/. Regardless of how the vowel is pronounced, however, the word has three syllables.

While the invention and use of the jer letters implies that the two high lax vowels were pronounced in the 9th century, subsequently the jers underwent the process known as jer-shift, or the fall of the jers. The details of this process, especially as it applies in different Slavic dialects/languages, are rather complicated, and what follows is a simplified description. The changes to the jers were different depending on their position in a word: in certain positions (called “weak”) the jers simply disappeared, whereas in other positions (called “strong”) the jers changed into vowels with lower articulation (exactly which vowel is subject to regional variation). Weak positions (or “weak jers”) are in a syllable followed directly by a syllable with a non-jer vowel and at the end of a word which is not followed by an enclitic; strong positions (or “strong jers”) are in a syllable directly preceding a syllable with a weak jer. Let’s illustrate this with a few examples, where weak jers are marked by italics and strong jers by boldface. Take the word ‘day’: its nominative singular form is dьnь and the genitive singular form is dьne. In accordance with the definitions given above, in the nominative form, the word-final jer is weak and the jer in the first syllable (preceding a syllable with a weak jer) is strong. In the genitive form, the jer in the first syllable is weak because it precedes a syllable with a non-jer vowel. Thus, a jer in the root may be either strong or weak, depending on the vowel in the grammatical ending. Another example is the word for ‘sleep’: its nominative singular form is sъnъ, with the word-final jer being weak and the jer in the preceding syllable (root) being strong. But in the genitive singular form sъna, the jer in the root is weak as it is followed by a syllable with a non-jer vowel.

In modern Russian, former strong front jers are pronounced as /e/ and former strong back jers as /o/. The weak jer, in accordance with the jer-shift, has been deleted. As a result, the OCS forms above correspond to день, pronounced /d’en’/, and дня, pronounced /dn’a/, for ‘day’, and сон, pronounced /son/, and сна, pronounced /sna/. Disregarding the issue of palatalization in the word ‘day’ for now, we can see that the weak word-final jer in the nominative form has been deleted, while the strong front jer turned into /e/ and the strong back jer in ‘sleep’ turned into /o/, while in the genitive forms of both words the jers in the root have been deleted. Thus, at the phonetic level (i.e. what we pronounce and hear) the jers were lost, but on a deeper, more abstract phonological level, they “survived as vowel/zero morphophonemes: under specific phonotactic conditions they are vowel phonemes, while under other conditions they are not pronounced—they are phonetic nulls” (Lunt 2001: 35, section 2.620). In other words, the process of jer-shift explains some of the vowel-zero (particularly, e/Ø and o/Ø) alternations in modern Russian, as in день/дня and cон/сна.

Let’s now consider some more complicated jer-syllable sequences. The rule of thumb is to count jers from the end of the word (including enclitic, if present): the last jer is weak, the one in the syllable immediately before it is strong, the one before a strong jer is again weak, etc. Non-jer vowels break this count: syllables with non-jer vowels can be effectively considered “end of the word”. Consider now the adjective from the noun ‘sleep’. In its nominative masculine singular form it is sъnьnъ: the last jer is weak, the middle jer is strong, and the first jer (i.e. the one in the root) is weak. In the feminine nominative singular, the ending is –a so the form is sъnьna: the jer in the second syllable is now weak because it precedes a syllable with a non-jer vowel, and the jer in the first syllable (i.e. in the root) is strong because it precedes a syllable with a weak jer.

Note that in OCS prepositions formed “an accentual unit together with the following noun” (Lunt 2001: 32, section 2.31). Similarly, the two demonstrative pronominal forms tъ ‘that’ and sь ‘this’, as well as the accusative singular masculine pronoun jь ‘him’, functioned as enclitics “forming an accentual unit with the noun or verb they followed” (ibid). For purposes of jer-shift, these elements were considered part of the same word that they preceded or followed. For instance, take vъ tьmě ‘in the dark’. The front jer in the noun root is weak as it precedes a syllable with a non-jer vowel, but the back jer in the preposition is strong: although it is at the end of the preposition itself, it is not considered to be word-final; prepositions are “lumped” with following nouns, hence the jer in the preposition precedes a syllable with a weak jer and is therefore strong. Similarly, in rabъ tъ ‘that slave’, the back jer in the demonstrative pronoun is weak (because it is word-final), but the back jer in the ending of the noun is considered strong because it is followed by an enclitic that contains a weak jer.

One last point to mention is that the process of jer-shift did not occur in the same way in positions that can be schematized as Cr_C/Cl_C, that is where jers (either front or back) followed a consonant plus “r” or “l” and preceded another consonant. This exceptional nature of these contexts explains the lack of parallelism in modern Russian between ljubov’/ljubvi ‘love’ (nominative singular vs. genitive singular) and krov’/krovi ‘blood’ (nominative singular vs. genitive singular). Although the nominative singular forms of the two words rhyme, the genitive forms do not. In the genitive form of ‘love’ the /o/ disappears, but in the genitive form of ‘blood’ it is retained. This is because in ‘blood’ but not in ‘love’ the /o/, corresponding to a back jer in OCS, follows an “r”. The word svekrov’ ‘mother-in-law’ (to a woman) also retains the /o/, which is a reflex of the back jer in OCS, in the genitive: svekrovi. In contrast, the word tserkov’ ‘church’ loses the /o/ in the genitive form tserkvi because it is not adjacent to an “r”.

For more details on the jers and jer-shift, see Lunt (2001: 34-40, sections 2.6-2.65).

Now we can reconsider the puzzle from the beginning of this post: the “disappearing vowel” (in Russian: беглая гласная) in the words ‘carpet’, ‘marquee’, ‘father’, ‘day’, ‘stump’, and ‘lion’ corresponds to a weak jer in Old Church Slavonic and Old Russian—its disappearing act is due to the fall of the jers. What about the exceptional words that retain their root vowels? The word šof’or ‘chauffeur’ was borrowed into Russian from French long after the fall of the jers; its /o/ does not correspond to an earlier weak jer, and hence the vowel-zero alternation does not apply.

The story of ‘forest’ is different. (Note especially the minimal pair l’ev/l’v-a ‘lion’ but l’es/l’es-a ‘forest’!) This word’s history in Slavic is long enough for it to have an OCS reflex. But that OCS word did not have a jer in the root; instead, it featured a different vowel, written in Cyrillic as ѣ (called “yat’”). In OCS that vowel was pronounced as /æ/ (in Roman transliteration it is typically represented as ě). In Russian this vowel was gradually raised and eventually merged with e. When exactly this change happened is a topic of debate, with most Russian scholars agreeing that it happened some time in the 18th century. It is also possible, even likely, that the merger happened at different times in different regional dialects. By the turn of the 20th century both were pronounced exactly the same, creating a problem for many a schoolboy (and girl) learning to spell; Lev Uspensky in his popular linguistics book A Word On Words («Слово о словах») called the letter “yat’” “the monster-letter, the scarecrow-letter […] which was washed with the tears of countless generations of Russian schoolchildren”. The orthography reform of 1918 finally eliminated the letter “Yat’” from the Russian alphabet, although the actual use of the letter continued for some time, as discussed in my earlier post.

The modern Russian words from the puzzle and their corresponding OCS or Old Russian forms (based on Fasmer’s etymological dictionary) are summarized in the table below:

Russian words (in transcription) Russian words (in Cyrillic) OCS/Old Russian form (in transliteration) OCS/Old Russian form (in Cyrillic) translation
kov’or ковёр kovьrъ ковьръ ‘carpet’
šat’or шатёр šatьrъ шатьръ ‘marquee’
šof’or шофёр ‘chauffeur’
ot’ec отец otьcь отьць ‘father’
d’en’ день dьnь дьнь ‘day’
p’en’ пень pьnь пьнь ‘stump’
l’ev лев lьvъ львъ ‘lion’
l’es лес lѣsъ лѣсъ ‘forest’




Lunt, Horace G. (2001) Old Church Slavonic Grammar. Mouton de Gruyter.

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