Other Irregular Nouns to Know | Czech Grammar

By the time you reach B2 you have met the big-name irregulars one by one — the body-part duals, dítě → d ěti, člověk → lidé. This page is the "everything else" drawer: the high-frequency nouns that don't fit any of the named exception classes but still misbehave in ways that trip up advanced learners. Three patterns dominate here — a productive neuter type (zvíře), a single sweeping stem-vowel shift (ů → o), and a couple of plural-only oddities like peníze ("money"). None of them is hard once you see the pattern, but each one quietly catches people who think they have "finished" the noun.

zvíře: the kuře type for animals

The neuter noun zvíře ("animal") is not a one-off — it belongs to a small, semantically tidy class of neuters that insert -et-/-ět- before the singular endings and switch to a collective -at- plural. This is the same ku ře pattern you met with kuře ("chick") and dítě in the singular: the class is built for the young of animals and, by extension, for animals in general.

Case	Singular	Plural
Nominative	zvíře	zvířata
Genitive	zvířete	zvířat
Dative	zvířeti	zvířatům
Accusative	zvíře	zvířata
Locative	(o) zvířeti	(o) zvířatech
Instrumental	zvířetem	zvířaty

The trap is the genitive plural zvířat — a bare stem with no ending, just like kuřat and the whole zero-ending genitive plural family. English speakers reach instinctively for zvířatů by analogy with the dative; resist it.

V té rezervaci žije přes dvě stě druhů zvířat.

Over two hundred species of animals live in that reserve. (zvíře → zvířat, genitive plural)

Děti se v zoo nejvíc těšily na velká zvířata.

At the zoo the kids were most excited about the big animals. (zvíře → zvířata, accusative plural)

Tomu zraněnému zvířeti se už daří líp.

That injured animal is doing better now. (zvíře → zvířeti, dative singular)

A handful of learned neuters: drama, téma

Words borrowed from Greek through Latin — drama, téma ("theme/topic"), dilema, klima — look like feminine -a nouns but are neuter, and they slot in a hidden -at- before plural and oblique endings: téma → tématu, téma → témata, dramatu, dramata. This is the same insert as zvíře, minus the -et- singular. The pitfall is treating téma as a žena-type feminine (*o tému); it is o tématu, neuter.

Probrali jsme všechna témata kromě toho posledního.

We covered every topic except the last one. (téma → témata, neuter plural with the -at- insert)

Ke každému tématu si připrav pár otázek.

Prepare a few questions for each topic. (téma → tématu, dative singular)

The big one: the ů → o stem shift

Here is the single most useful pattern on the page, because it recurs across some of the commonest masculine and feminine nouns in the language. A noun whose nominative singular contains a long ů (the ů s kroužkem, the ring-u) typically shortens it to a short o the moment any ending is added — that is, in every case except the bare nominative (and the homophonous accusative of inanimates).

Nominative	Meaning	Genitive sg.	Other forms
dům	house	domu	v domě, domy, domů
stůl	table	stolu	na stole, stoly, stolů
vůz	car / cart	vozu	ve voze, vozy, vozů
kůň	horse	koně	na koni, koně, koní
sůl	salt	soli	v soli, soli
nůž	knife	nože	nožem, nože, nožů
důvod	reason	důvodu (no shift!)	— see below

The logic is historical: that ů descends from an old long ō that survived only when it landed in a closed final syllable (the bare nominative dům). Once a vowel ending pulls the syllable boundary, the old length collapses to a plain short o. You don't have to know the history to use it — but it explains why the alternation is so regular. Expect the long ů to vanish whenever you add an ending. Modelling that one expectation correctly fixes dům, stůl, vůz, kůň, sůl, nůž, hůl (cane), vůl (ox), bůh → boha (god) and more in one stroke.

Před naším domem parkuje cizí auto.

There's a strange car parked in front of our house. (dům → domem, instrumental)

Polož to na stůl, ale ne moc blízko ke kraji stolu.

Put it on the table, but not too close to the edge of the table. (stůl → stolu, genitive)

Přidej do té polévky trochu soli.

Add a bit of salt to that soup. (sůl → soli, genitive after a quantity)

Na koni jezdím od dětství.

I've ridden horses since childhood. (kůň → koni, locative)

💡

Treat ů → o as a reflex, not a list to memorise. The instant an ending appears, the ring-u becomes a short o: dům → domu, stůl → stolu, vůz → vozu, sůl → soli. Keeping the long ů (*důmu) is the surest sign of an English speaker who learned the word from the dictionary form alone.

When ů does NOT shift

Not every ů alternates — only the ones that are part of the historically alternating stem. In důvod ("reason"), vůně ("scent"), růže ("rose"), kůra ("bark/crust"), půl ("half") the ů is stable: důvodu, vůně, růže, kůry, půlky. There is no derivational test you can apply from outside; you simply learn that the everyday short words (dům, stůl, vůz, kůň, sůl, nůž, vůl, bůh) shift, while many longer or younger words keep their ů. When in doubt, the alternation is far more common among monosyllables.

Z jakého důvodu jsi tam vůbec chodil?

What reason did you even go there for? (důvod → důvodu — no shift)

peníze: money is plural, and its genitive is a shock

Peníze ("money") is a plurale tantum — it exists only in the plural, and it takes plural agreement throughout (peníze jsou, "money is/are", literally plural). The reason is concrete: a peníz once meant a single coin, so "money" is grammatically "coins". The form everyone gets wrong is the genitive plural peněz, where the í shortens to ě and there is no ending at all.

Case	Form
Nominative	peníze
Genitive	peněz
Dative	penězům
Accusative	peníze
Locative	(o) penězích
Instrumental	penězi

The genitive peněz turns up constantly, because Czech uses the genitive after expressions of quantity and after the preposition bez ("without"): hodně peněz ("a lot of money"), bez peněz ("without money"). And the instrumental is the bare penězi, not the regular *penízemi.

Na nové auto zatím nemám dost peněz.

I don't have enough money for a new car yet. (peníze → peněz, genitive after dost)

Vyrazili jsme do města úplně bez peněz.

We headed into town with no money at all. (bez + genitive: peněz)

S takovými penězi si můžeš dovolit, co chceš.

With that kind of money you can afford whatever you want. (peníze → penězi, instrumental)

💡

Two money traps in one word: peníze is always plural (so peníze jsou, never *peníze je), and its genitive is the irregular peněz (í → ě, zero ending). You will reach for that genitive every time you say "a lot of / not enough / without money".

Common Mistakes

❌ V kleci bylo pět malých zvířatů.

Incorrect — the genitive plural of zvíře is the bare-stem zvířat, not *zvířatů.

✅ V kleci bylo pět malých zvířat.

There were five small animals in the cage. (zvíře → zvířat)

❌ Bydlíme v starém důmu na náměstí.

Incorrect — the ů shortens to o once an ending is added: domě (locative).

✅ Bydlíme ve starém domě na náměstí.

We live in an old house on the square. (dům → domě)

❌ Sedni si ke stůlu.

Incorrect — stůl shifts to stol- before endings: ke stolu (dative).

✅ Sedni si ke stolu.

Sit down at the table. (stůl → stolu)

❌ Nemám dost penízů.

Incorrect — the genitive plural of peníze is the irregular peněz, with í → ě and no ending.

✅ Nemám dost peněz.

I don't have enough money. (peníze → peněz)

❌ Ty peníze je na stole.

Incorrect — peníze is plural, so the verb is plural: peníze jsou.

✅ Ty peníze jsou na stole.

The money is on the table. (peníze jsou — plural agreement)

Key Takeaways

zvíře follows the kuře type: singular -et- (zvířete), collective plural -at- (zvířata), with the bare-stem genitive plural zvířat.
Learned neuters like téma, drama insert -at- too and stay neuter (tématu, témata), despite the -a ending that looks feminine.
The ů → o stem shift is a single reflex covering dům → domu, stůl → stolu, vůz → vozu, kůň → koně, sůl → soli, nůž → nože: the ring-u shortens the moment any ending appears. Keeping the long ů (*důmu) is the classic English-speaker error.
Some words keep a stable ů (důvod, vůně, růže); there's no outside test, but the alternation clusters in short, common words.
peníze ("money") is plural-only with plural agreement, and its genitive is the irregular peněz (í → ě). For the wider class, see pluralia tantum; for the ů/ú spelling split, see ů with a ring vs ú with an acute.

Now practice Czech

Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.

Start learning Czech→