Genitive Plural of Russian Nouns

Родительный Падеж Множественного Числа Существительных

Under Construction

The Genitive Plural of nouns in Russian is the most complex case to form. There are many rules (and many exceptions), which I haven't found fully listed anywhere. Therefore, I try to give here a comprehensive list, along with examples.

In nouns having the same stem for the singular and plural (other than accent), the Genitive Plural is generally based on the Nominative Singular. However, in nouns with a different plural stem (irregular plurals) it is based on the Nominative Plural and formed a bit differently.

Regular Plurals

The basic case-endings are as follows (as described here), for the most part regardless of gender and accent^*:

* Other than the regular correlation between gender and Nominative Singular ending.

Nominative Singular ends in … Genitive Plural ending Example

Hard consonant or й -ов стол → столов table, m.

Soft consonant or sibilant (ш ж щ ч) -ей дверь → дверей door, f.
врач → врачей doctor, m.

Any vowel null ending (remove the vowel) книга → книг book, f.
слово → слов word, n.

Nominative Singular ends in …	Genitive Plural ending	Example
Hard consonant or й	-ов	стол → столов table, m.
Soft consonant or sibilant (ш ж щ ч)	-ей	дверь → дверей door, f. врач → врачей doctor, m.
Any vowel	null ending (remove the vowel)	книга → книг book, f. слово → слов word, n.

Nouns ending in ь + accented vowel take -ей rather than the null ending: семья → семей family, питьё → питей a drink, beverage
The same goes for most nouns ending in a sibilant + accented vowel: свеча → свечей candle
Most diminutives in -це may take either the null ending or -ов (changing into -ев due to spelling rules): оконце → оконец / оконцев from окно window

Exceptions: a few hard-consonant stems take the null ending instead of -ов, resulting in the Genitive Plural being identical to the Nominative Singular.
Many vowel stems in which the last consonant is soft also take -ей instead of the null ending.
A few (neuter) nouns in -ье/-ьё take -ьев/-ьёв rather than the null ending, which would have resulted in -ий/-ей respectively.

The -ов ending

This ending changes according to the usual rules of combination and spelling:

Unaccented, combined with й: случай → случаев case, occurence
Accented, combined with й: край → краёв edge
Unaccented after ц: месяц → месяцев month
Accented after ц - unchanged: чтец → чтецов reader

The -ей ending

This ending is completely regular; the only thing to note is perhaps the regular dropping of -ь when using it, as seen in the examples above.

The null ending

This ending has several sub-cases worthy of note, depending on how the Nominative Singular ends:

soft consonant + vowel a soft sign remains неделя → недель week

vowel + soft vowel the last vowel is replaced with -й здание → зданий building

ь + unaccented vowel both are replaced with -ий печенье → печений cookie (analogous to the above case)

If a consonant cluster precedes the final vowel, a fleeting vowel may appear before the last consonant in the cluster: поездка → поездок trip. See the next section.

Fleeting Vowels

Fleeting vowels may appear in Russian whenever the null ending is used. This occurs also in the Nominative Singular - but isn't a problem since this is the dictionary form of the noun - and in short-form masculine adjectives. In the latter case the rules are similar to those of the Genitive Plural, but not identical.

The correct use of fleeting vowels encompasses two questions:

1. Which vowel to use

If either of the last two consonants is a velar (к г х), use о, as in поездка above or окно → окон window
Otherwise, use е – even if the preceding consonant is hard: кресло → кресел armchair
О may of course change into е due to the standard spelling rules:

Following a sibilant: чашка → чашек cup
Following a soft consonant: галька → галек pebble
Combining with й: чайка → чаек seagull

Exceptions: a handful of nouns use ё or и instead
(I've encountered the claim that ё is generally inserted and just becomes е when unaccented, but accented е also occurs, and I haven't found enough examples overall to generalize).

2. Whether a fleeting vowel appears or not

* I've found no explicitly stated rule regarding this; the following conclusions are based on the results of online morphological analysers. Location of accent and perceived ease of pronunciation seem not to play a part.

A fleeting vowel generally appears if and only if the final consonant is к, л, н, ц (including soft counterparts):

туфля → туфель shoe	утро → утр morning
кольцо → колец ring	лекарство → лекарств medicine
кукла → кукол doll	ведьма → ведьм witch
весна → вёсен spring (season)

No vowel appears between double consonants: ванна → ванн bath
The majority of nouns in -ня also harden the н (in the Genitive Plural only): песня → песен song
A dozen nouns or so, mostly outdated, consist of only a consonant cluster followed by a vowel. Removing the vowel and leaving just the asyllabic stem is too much even for Russian… so these nouns use a fleeting vowel, the ending -ей or avoid the Genitive Plural altogether: сто → сот hundred, тля → тлей aphid

Exceptions: rarely, a fleeting vowel doesn't appear before the above consonants.
In a quite a few nouns, however, a fleeting vowel does appear before б, г, м or р, though this is still the minority of cases.

Irregular Plurals

As mentioned above, the Genitive Plural is based on the plural stem if that differs from the singular. Therefore, this section always specifies the Nominative Plural in addition to the Nominative Singular and Genitive Plural.

A sizeable group of nouns form their Nominative Plurals with the ending -ья. These have special rules:

Accented -ья is replaced with -ей: друг → друзья → друзей friend
Unaccented -ья is replaced with -ьев: перо → перья → перьев feather

The following classes of nouns always form the Genitive Plural with the null ending:

Class	Nom. Sg.	Nom. Pl.	Gen. Pl.	English	Comments
Neuters in -мя (н-stems)	имя	имена	имён	name	Here the stem in -мен is also used in the singular cases other than the Nom./Acc.
Young of animals or humans in -ёнок	котёнок	котята	котят	kitten	From кот cat
Nationality, origin or social class in -нин	гражданин	граждане	граждан	citizen	The plural stem ends in a hard н (e.g. the Dative Plural is гражданам). This also pertains to most other nouns in -ин, which are somewhat irregular.

Otherwise, the Genitive Plural ending is difficult to predict - including pluralia tantum (nouns with only plural forms), where it is possibly based on a historical singular form. The null ending seems to be the predominant one, though.

Sources

The alphaDictionary Website (Site Contents)

George Mitrevski's Russian Grammar Tutorials (Tutorials Index.)

Morphology: Russian Wiktionary and online versions of Zaliznyak's Grammatical Dictionary (links at bottom)

soft consonant + vowel	a soft sign remains	неделя → недель week
vowel + soft vowel	the last vowel is replaced with -й	здание → зданий building
ь + unaccented vowel	both are replaced with -ий	печенье → печений cookie (analogous to the above case)