The Three Declensions: Overview

Russian has six cases, but it does not have six separate sets of endings to memorize — it has three declension classes, and which class a noun belongs to is decided almost entirely by its gender and its nominative-singular ending. Learn the class, check whether the stem is hard or soft, and you can predict the noun's entire six-case paradigm. This page is the map: it names the three classes, gives one clean model noun for each, and lays out the full singular paradigm side by side so you can see the shape of a Russian noun all at once. It deliberately stops at the forms — what each case is for (who does the seeing, what follows which preposition) lives in the Cases group, starting with choosing the case.

Why three classes, and how to assign a noun

The traditional Russian school grammar (the one every native speaker learns) groups nouns by the endings they take, not by gender directly — though gender is what mostly decides the grouping. Here is the assignment rule:

Notice what the numbering is not: it is not a difficulty ranking and it does not line up neatly with gender. The first declension is the one that contains the "-а words" regardless of whether they name a woman (ма́ма "mum"), a man (па́па "dad", дя́дя "uncle"), or a thing (неде́ля "week", кни́га "book"). The second declension is the biggest class, holding the consonant-final masculines (стол "table", конь "horse", музе́й "museum") and every neuter (окно́ "window", мо́ре "sea"). The third declension is small and exclusively feminine: nouns ending in the soft sign -ь, such as ночь "night", дверь "door", and мать "mother".

The whole shape at once: one noun from each class

Most courses teach Russian case-by-case — here are all the genitives, now all the datives — and that order quietly hides the thing a learner most needs to feel: the paradigm, the full set of forms one word runs through. Below is the entire singular of one model noun from each declension, all six cases stacked together. Read each column top to bottom and you are seeing the actual "silhouette" of a Russian noun, including where the stress sits across it.

Three things jump out of this picture. First, the third declension is the most economical: ночь shows only two distinct forms in the singular — ночь (nom./acc.) and но́чи (gen./dat./prep.), plus the instrumental но́чью. Second, стол keeps its stress on the ending throughout the oblique cases (стола́, столу́, столо́м, столе́) — its stress is "mobile," jumping off the one-syllable nominative onto every ending; this stress behaviour is itself part of the paradigm, covered in noun stress patterns. Third, the accusative is never an independent form here: ма́му borrows a dedicated feminine -у, while стол and ночь copy the nominative (because both happen to be inanimate).

Class plus stem-type predicts everything

The class tells you which slot of endings a noun uses; one more piece of information — whether the stem is hard or soft — tells you which letter fills that slot. A hard stem takes the hard vowel (-а, -ы, -у, -о), a soft stem takes its soft mirror (-я, -и, -ю, -е). Compare two first-declension nouns, one hard, one soft:

The two paradigms are the same shape — the soft column is just the hard column with each vowel softened. This is the whole reason Russian declension is learnable: you are not memorizing six classes times two stem-types as twelve unrelated lists; you are learning three shapes and one hard↔soft conversion. The mechanics of that conversion (and the spelling rules that occasionally override it) are on hard vs soft stems.

English has nothing like this

English nouns barely inflect: we add -s for the plural and -'s for possession, and that is the entire system — table, tables, table's. There is no notion that "table" might wear a different ending depending on whether it is the subject, the object, or the thing you are talking about. Russian assigns every noun a full inflectional career across six cases, and the declension class is the timetable for that career. The closest English analogue is the pronoun: he / him / his changes shape by role exactly the way стол / стол / стола́ does — and just as you would never say "I saw he", a Russian would never leave a noun in the nominative where the sentence calls for the genitive. The difference is only that Russian does to every noun what English does to a tiny handful of pronouns.

What this page leaves to other pages

This is a map, not the territory. Three things are deliberately handled elsewhere:

• The plural. The classes above describe the singular. Plural endings cut across the three classes and are gathered, alongside the singular, in the case-endings master table.
• What each case does. Why the genitive marks possession, why the prepositional follows о and на — that is meaning, not form, and it lives in the Cases group (start at six cases, one noun). The deep paradigms with every spelling sub-rule are in first, second, and third declension detail.
• The irregulars. A small set of nouns refuses to fit. The neuter nouns in -мя (и́мя, вре́мя) insert an extra -ен- and get their own page; the unique masculine путь is a class of one.

Common Mistakes

Key Takeaways

• Russian sorts most nouns into three declension classes: 1st (feminine and masculine in -а/-я: ма́ма, па́па, неде́ля), 2nd (zero-ending masculines and all neuters: стол, конь, окно́, мо́ре), 3rd (feminine in -ь: ночь, дверь).
• The class is decided by the nominative-singular ending, not by the sex of the referent — which is why па́па (1st) and окно́ (2nd) sit where their endings put them.
• Class + hard/soft stem predicts the whole paradigm. A soft-stem noun is the hard-stem shape with each vowel softened (ма́ма / неде́ля).
• Seeing all six cases of one noun at once reveals the real shape: the 3rd declension is the leanest, стол shows mobile end-stress, and the accusative usually just copies the nominative or genitive rather than being its own form.
• This page is the map of forms; the meaning of each case, the plural, and the irregular -мя and путь nouns are covered on their own pages.