Most neuter nouns in Russian end in -о or -е. However, a small, ancient group of neuter nouns ends in -мя. The most common are время (time) and имя (name), but the group also includes words like семя (seed), пламя (flame), знамя (banner), and племя (tribe).
The Hidden "-мен-" Stem
These words have a special declension pattern. Whenever they change case (except for the Nominative and Accusative singular), the ending -я drops and the stem expands with the suffix -мен-.
| Case | Singular | Plural |
|---|
| Nominative / Accusative | время, имя | времена, имена |
| Genitive | времени, имени | времён, имён |
| Dative | времени, имени | временам, именам |
| Instrumental | временем, именем | временами, именами |
| Prepositional | времени, имени | временах, именах |
Note: The Genitive plural of семя is семян. Also, знамя shifts its stress to become знамёна in the Nominative and Accusative plural.
Singular Usage
In the singular, the Genitive, Dative, and Prepositional cases share the same ending: -и. The Instrumental case takes -ем. If the noun is the direct object (Accusative), it looks exactly like the dictionary form.
Plural Usage
In the plural, the expanded -мен- stem is always used, but the endings behave much more like regular nouns (-ам, -ами, -ах). Pay special attention to the Genitive plural, which drops the vowel ending entirely and usually ends in -мён (like имён or племён).