Greek declension is unusually tidy. Learn the ten or so regular classes and you can inflect the overwhelming majority of the dictionary without looking anything up. The price of that tidiness is a short list of exceptions — and, with the perversity that language always shows, the exceptions are among the most frequent words you will ever use: milk, meat, light, mind, child, hand, woman.
This page collects them. There is no clever trick here, and pretending otherwise would waste your time: these forms are memorised, not derived. What this page can do is show you the shape of the irregularity, because once you see that a noun like το φως is running two paradigms at once, the forms stop looking random and start looking like the fossils they are.
Heteroclisis: one noun, two paradigms
The technical name for the main phenomenon is heteroclisis — from Greek heteros "other" + κλίνω "to inflect". A heteroclitic noun takes some of its forms from one declension pattern and the rest from another, usually because the word survived a change in the language and different parts of it were preserved from different periods.
το φως ("light") is the textbook case. Its singular is a learned neuter with a hidden dental stem φωτ-, built on the same pattern as το γεγονός → του γεγονότος in the table below; its plural behaves like an ordinary neuter in -ο:
| Case | Singular (learned type) | Plural (demotic type) |
|---|---|---|
| Nominative | το φως | τα φώτα |
| Genitive | του φωτός | των φώτων |
| Accusative | το φως | τα φώτα |
Notice that the genitive singular του φωτός is stressed on the ending while the plural τα φώτα pulls the stress back. Two paradigms, two stress behaviours, one word.
One distinction worth drawing now, because the two types look similar on the page and behave differently: φως is not one of the learned neuters in -ος such as το κράτος, το μέρος, το έθνος. Those take -ους in the genitive (του κράτους, του μέρους) and have their own page — see Other Learned Neuters. φως belongs with το γεγονός and το καθεστώς: neuters whose stem ends in a dental (φωτ-, γεγονοτ-, καθεστωτ-), giving του φωτός, του γεγονότος, του καθεστώτος.
Άναψε το φως, δεν βλέπω τίποτα εδώ μέσα.
ánapse to fos, dhen vlépo típota edhó mésa
Turn on the light, I can't see a thing in here.
Ταξιδεύει με την ταχύτητα του φωτός.
taksidhévi me tin tachítita tu fotós
It travels at the speed of light.
Έσβησαν τα φώτα σε όλη τη γειτονιά.
ésvisan ta fóta se óli ti yitoniá
The lights went out across the whole neighbourhood.
The hidden-stem neuters
A family of very common neuters looks short and simple in the nominative and then produces an extra syllable the moment you need a genitive or a plural. The extra material is the old Ancient Greek stem, which the nominative had worn away:
| Nominative sg. | Genitive sg. | Nominative pl. | Genitive pl. | Hidden stem |
|---|---|---|---|---|
| το γάλα | του γάλακτος / γάλατος | τα γάλατα | των γαλάτων | γαλακτ- / γαλατ- |
| το κρέας | του κρέατος | τα κρέατα | των κρεάτων | κρεατ- |
| το τέρας | του τέρατος | τα τέρατα | των τεράτων | τερατ- |
| το φως | του φωτός | τα φώτα | των φώτων | φωτ- |
| το γεγονός | του γεγονότος | τα γεγονότα | των γεγονότων | γεγονοτ- |
το γάλα deserves its own note, because it has two competing genitives and the choice is a register choice. του γάλακτος is the older, learned form; it is what you see on packaging, in prices quoted on the news, and in every derivative (γαλακτοκομικά "dairy products", γαλακτομπούρεκο). του γάλατος is the everyday spoken form. Both are correct; a great many speakers dodge the problem entirely by rephrasing.
Η τιμή του γάλακτος ανέβηκε πάλι φέτος.
i timí tu ghálaktos anévike páli fétos
The price of milk has gone up again this year.
Τελείωσε το γάλα, θα πάρω αύριο το πρωί.
telíose to ghála, tha páro ávrio to proí
We're out of milk, I'll get some tomorrow morning.
Δεν τρώω κόκκινο κρέας εδώ και δύο χρόνια.
dhen tróo kókino kréas edhó ke dhío chrónia
I haven't eaten red meat for two years.
Οι τιμές των κρεάτων έχουν τρελαθεί.
i timés ton kreáton échun trelathí
Meat prices have gone completely mad.
ο νους: a contracted masculine
ο νους ("mind") is the shrunken survivor of Ancient Greek νόος. Its singular is minimal — του νου, τον νου — and it is overwhelmingly used in the singular, mostly in fixed expressions. A learned plural οι νόες / των νόων exists and turns up in essays and obituaries about "great minds" (academic, literary), but you will not hear it in a café.
| Case | Singular | Plural (learned) |
|---|---|---|
| Nominative | ο νους | οι νόες |
| Genitive | του νου | των νόων |
| Accusative | τον νου | τους νόες |
Δεν μου φεύγει από τον νου αυτό που είπε χθες.
dhen mu févyi apó ton nu aftó pu ípe chthes
I can't get what he said yesterday out of my head.
The expressions worth learning whole are έχε τον νου σου ("keep an eye out"), βάλε στο νου σου ("bear in mind") and δεν μου πάει ο νους ("it doesn't occur to me"). Note that the accusative keeps the -ν of the article: τον νου, never ×το νου, since το would make it neuter.
Έχε τον νου σου στα παιδιά όσο λείπω.
éche ton nu su sta pedhiá óso lípo
Keep an eye on the kids while I'm out.
Βάλε στο νου σου ότι δεν θα προλάβουμε να γυρίσουμε απόψε.
vále sto nu su óti dhen tha prolávume na yirísume apópse
Bear in mind that we won't make it back tonight.
The -ι neuters and their extra syllable
το παιδί and το χέρι are not irregular in the strict sense — they follow the neuter -ι pattern faithfully — but they trip up nearly every learner, so they belong here. The pattern is that an extra -ι- surfaces before the genitive and plural endings:
| Case | το παιδί (stressed -ί) | το χέρι (unstressed -ι) |
|---|---|---|
| Nom. sg. | το παιδί | το χέρι |
| Gen. sg. | του παιδιού | του χεριού |
| Nom. pl. | τα παιδιά | τα χέρια |
| Gen. pl. | των παιδιών | των χεριών |
The one thing to internalise: the plural is stressed where the singular was stressed. παιδί has its accent on the final syllable, so the plural is παιδιά; χέρι has it on the first, so the plural is χέρια. But both genitives jump onto the ending — του παιδιού, του χεριού — because those endings are historically long and drag the accent to them.
Τα παιδιά έφυγαν για το σχολείο πριν από μισή ώρα.
ta pedhiá éfighan ya to scholío prin apó misí óra
The kids left for school half an hour ago.
Πλύνε τα χέρια σου πριν καθίσεις στο τραπέζι.
plíne ta chéria su prin kathísis sto trapézi
Wash your hands before you sit down at the table.
Το δωμάτιο των παιδιών είναι πάνω αριστερά.
to dhomátio ton pedhión íne páno aristerá
The kids' room is upstairs on the left.
The tiny closed class of neuters in -υ works similarly but with its own quirks: το βράδυ → του βραδιού, τα βράδια; το δάκρυ → τα δάκρυα, genitive singular του δακρύου. That last form is the standard one, not a formal alternative — the demotic του δακριού, built by analogy with του βραδιού, is heard (informal) but written far less often. In practice you will meet the plural τα δάκρυα a hundred times for every genitive singular.
Τα βράδια εδώ κάνει ψύχρα ακόμα και τον Αύγουστο.
ta vrádhia edhó káni psíchra akóma ke ton Ávghusto
Evenings here get chilly even in August.
η γυναίκα and the γυναικ- stem
η γυναίκα declines regularly as a feminine in -α — της γυναίκας, οι γυναίκες, των γυναικών — but it carries a visibly older stem, γυναικ-, and that stem is why the word behaves oddly outside the paradigm. It shows up in every derivative (γυναικείος "women's", γυναικολόγος, γυναικοπαρέα) and in the learned genitive singular της γυναικός, which survives in legal and formal prose (formal) but sounds absurd in conversation. The Ancient vocative γύναι survives only in biblical quotation (archaic).
Τα δικαιώματα των γυναικών κατακτήθηκαν με αγώνες.
ta dhikeómata ton yinekón kataktíthikan me aghónes
Women's rights were won through struggle.
Η γυναίκα που ρώτησες δουλεύει στο διπλανό γραφείο.
i yinéka pu rótises dhulévi sto dhiplanó ghrafío
The woman you asked about works in the next office.
Nouns that change gender in the plural
A striking sub-type of heteroclisis: a masculine singular that takes a neuter plural. ο χρόνος → τα χρόνια (years), ο λόγος → τα λόγια (words), ο πλούτος → τα πλούτη (riches). The noun is not switching gender for semantic reasons; the plural was simply inherited from a different pattern and stuck.
Πέρασαν δέκα χρόνια από τότε που τον είδα τελευταία φορά.
pérasan dhéka chrónia apó tóte pu ton ídha teleftéa forá
Ten years have gone by since I last saw him.
Several of these nouns keep a second, regular plural alongside — οι χρόνοι, οι λόγοι — with a completely different meaning. That is a big enough topic to have its own page: see Nouns With Two Plurals.
Defective nouns: missing a number
Finally, a set of nouns that are not irregular so much as incomplete. Some exist only in the plural:
- τα λεφτά (money), τα Χριστούγεννα (Christmas), τα γενέθλια (birthday), τα μεσάνυχτα (midnight), οι διακοπές (holidays), τα εγκαίνια (the opening ceremony).
Others are effectively singular-only, and the plural, where it exists at all, means "types of": η υγεία (health), το γάλα (τα γάλατα only means "kinds of milk"), ο καιρός in the sense of weather.
Δεν έχω λεφτά πάνω μου, πληρώνεις εσύ;
dhen écho leftá páno mu, plirónis esí;
I've got no money on me, will you pay?
Τα Χριστούγεννα θα είμαστε στο χωριό της γιαγιάς.
ta christúyena tha ímaste sto chorió tis yayás
At Christmas we'll be at grandma's village.
Common Mistakes
1. Using the bare nominative as a genitive. The hidden stem has to surface.
❌ Η τιμή του κρέας έχει διπλασιαστεί.
Incorrect — the genitive is του κρέατος, with the stem κρεατ-.
✅ Η τιμή του κρέατος έχει διπλασιαστεί.
i timí tu kréatos échi dhiplasiastí
The price of meat has doubled.
2. Pluralising φως as if it were regular. The plural jumps to the other paradigm.
❌ Έσβησα όλα τα φως πριν φύγω.
Incorrect — the plural of το φως is τα φώτα.
✅ Έσβησα όλα τα φώτα πριν φύγω.
ésvisa óla ta fóta prin fígho
I turned off all the lights before I left.
3. Writing the Ancient plural τα παιδία. It survives only in old texts and in the set phrase τα παιδία παίζει, quoted as a joke about pedantic Greek. Modern Greek says παιδιά.
❌ Τα παιδία παίζουν στην αυλή.
Incorrect in modern Greek — the plural is τα παιδιά (παιδία is Ancient/archaic).
✅ Τα παιδιά παίζουν στην αυλή.
ta pedhiá pézun stin avlí
The children are playing in the yard.
4. Moving the stress in the plural of χέρι. The plural keeps the singular's stress; only the genitive shifts.
❌ Έχω κρύα χεριά, δώσε μου τα γάντια.
Incorrect — the plural is τα χέρια, stressed on the first syllable.
✅ Έχω κρύα χέρια, δώσε μου τα γάντια.
écho kría chéria, dhóse mu ta ghándia
My hands are cold, pass me the gloves.
5. Making a plural-only noun singular. τα λεφτά has no singular in this meaning.
❌ Δεν έχω αρκετό λεφτό για το εισιτήριο.
Incorrect — the noun is plural-only: δεν έχω αρκετά λεφτά.
✅ Δεν έχω αρκετά λεφτά για το εισιτήριο.
dhen écho arketá leftá ya to isitírio
I haven't got enough money for the ticket.
Key Takeaways
- Heteroclisis = one noun drawing forms from two paradigms. το φως is the model: learned singular (φως / φωτός), demotic plural (τα φώτα).
- Short neuters hide a longer stem that surfaces in the genitive and plural: γάλα → γάλακτος / γάλατα, κρέας → κρέατος / κρέατα, τέρας → τέρατος, γεγονός → γεγονότος.
- του γάλακτος is learned and used in writing and derivatives; του γάλατος is the everyday spoken genitive.
- ο νους is a contracted masculine: του νου, τον νου; the plural οι νόες is academic and rare.
- Neuters in -ι insert an extra -ι- before the ending: του παιδιού / τα παιδιά, του χεριού / τα χέρια. The plural keeps the singular's stress; the genitive always moves it to the ending.
- Some masculines take a neuter plural — ο χρόνος → τα χρόνια, ο λόγος → τα λόγια — and often keep a second, regular plural with a different meaning.
- Defective nouns lack a number entirely: τα λεφτά, τα Χριστούγεννα, οι διακοπές are plural-only and take plural agreement.
Now practice Greek
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Start learning Greek →Related Topics
- Nouns With Two PluralsB2 — A set of common nouns — χρόνος, λόγος, δεσμός, βράχος, χείλος — that build two different plurals, where picking the wrong one does not sound clumsy but says something else entirely.
- Other Learned NeutersC1 — The residual learned neuters whose true stem hides until you decline them — το φως / του φωτός / τα φώτα, το κρέας / του κρέατος, το γάλα / του γάλακτος, and the participial neuters το καθήκον, το προϊόν, το παρόν, το μέλλον, το γεγονός, το ον. Everyday words with irregular stems you simply have to learn.