English some is a single word doing at least four jobs: some friends (a few countable ones), some bread (an unspecified amount), some man phoned (one person, identity unknown), and some people say (an unidentified subset). Greek splits that work across three words, and the split is not arbitrary — it follows number and identifiability. μερικοί counts a handful, and only ever in the plural. κάποιος singles out one unidentified individual, and declines like an adjective. κάτι is invariable and, in speech, spreads well beyond "something".
Why Greek needs these words at all
The indefinite article ένας / μια / ένα has no plural — there is no Greek "a-s". So while a friend is ένας φίλος, the plural of that phrase is simply φίλοι, with nothing marking indefiniteness at all. That leaves a real gap: how do you say some friends, as opposed to friends in general or the friends? The answer is that μερικοί, κάποιοι and κάτι fill the plural-indefinite slot that the article cannot reach. Leaving them out is not an error — a bare plural (Ήρθαν φίλοι, "friends came") is perfectly good Greek — but it says less: it asserts that the thing happened without measuring or characterising the group. The behaviour of the article itself is on uses of the indefinite article.
μερικοί: some, and plural only
μερικοί / μερικές / μερικά means some, a few — a small but non-trivial number of countable things. It inflects for gender and case in the plural (μερικών, μερικούς) and it takes a bare noun, never the article.
Μερικοί συμμαθητές μου δεν έχουν αποφασίσει ακόμα τι θα σπουδάσουν.
merikí simathités mu dhen échun apofasísi akóma ti tha spudhásun
Some of my classmates still haven't decided what they're going to study.
Πήρα μερικές φωτογραφίες από το μπαλκόνι, θα σου τις στείλω.
píra merikés fotoghrafíes apó to balkóni, tha su tis stílo
I took a few photos from the balcony — I'll send them to you.
Έχω μερικά ρούχα να σιδερώσω και μετά είμαι έτοιμη.
écho meriká rúcha na sidheróso ke metá íme étimi
I've got a few things to iron and then I'm ready.
The crucial restriction: as a quantifier, μερικοί exists only in the plural. ×μερικός άνθρωπος for "some person" is not Greek — you want κάποιος άνθρωπος. And because a mass noun is singular, μερικοί cannot quantify one either: for some milk you say λίγο γάλα or just bare γάλα, never ×μερικό γάλα. The graded quantifiers that do handle mass nouns are on πολύς, λίγος, αρκετός.
There is, however, a genuine singular μερικός — it just means something else. μερικός / μερική / μερικό in the singular is the adjective partial, and it is alive in fixed modern collocations: μερική απασχόληση ("part-time employment"), μερική κάλυψη ("partial insurance cover"), and the weather-forecast adverb μερικώς ("partly", as in μερικώς νεφελώδης, partly cloudy) which is (formal).
Δουλεύει με μερική απασχόληση από τότε που έκανε παιδί.
dhulévi me merikí apaschólisi apó tóte pu ékane pedhí
She's been working part-time since she had a baby.
κάποιος: "some ... or other"
κάποιος picks out one referent whose identity is unknown or irrelevant, and it declines fully, like an ordinary adjective.
| Masculine | Feminine | Neuter | |
|---|---|---|---|
| Nom. sg. | κάποιος | κάποια | κάποιο |
| Gen. sg. | κάποιου | κάποιας | κάποιου |
| Acc. sg. | κάποιον | κάποια | κάποιο |
| Nom. pl. | κάποιοι | κάποιες | κάποια |
| Gen. pl. | κάποιων | κάποιων | κάποιων |
| Acc. pl. | κάποιους | κάποιες | κάποια |
Κάποιος συνάδελφος άφησε το φως αναμμένο όλη τη νύχτα.
kápios sinádhelfos áfise to fos anaméno óli ti níchta
Some colleague or other left the light on all night.
Θα βρω κάποιον τρόπο να σε βοηθήσω, μην ανησυχείς.
tha vro kápion trópo na se voithíso, min anisichís
I'll find some way to help you — don't worry.
Με πήρε κάποια κυρία από την τράπεζα και δεν κατάλαβα τι ήθελε.
me píre kápia kiría apó tin trápeza ke dhen katálava ti íthele
Some woman from the bank rang me and I didn't understand what she wanted.
Used without a noun, κάποιος is the pronoun somebody, and the plural κάποιοι means some people — but not quite the same some people as μερικοί. μερικοί measures a subset by size ("a few of them, not all"); κάποιοι points at unidentified individuals, often with a knowing edge, the way English certain people does. Κάποιοι λένε ότι… is the standard opening for "there are those who say…". The pronoun side of both words is on indefinite pronouns.
Κάποιοι ήρθαν και έφυγαν πριν καλά καλά αρχίσει η γιορτή.
kápii írthan ke éfighan prin kalá kalá archísi i yortí
Some people turned up and left before the party had properly started.
Κάποια μέρα θα σου εξηγήσω τι έγινε τότε.
kápia méra tha su eksiyíso ti éyine tóte
One day I'll explain to you what happened back then.
κάποιος or ένας? A question of whether identity matters
Both ένας φίλος and κάποιος φίλος translate as a friend / some friend, and choosing between them is one of those small decisions that makes speech sound native. ένας introduces a referent the speaker has in mind and may well go on to talk about. κάποιος signals that the identity is unknown to the speaker, or that it does not matter.
Με πήρε ένας δικηγόρος σήμερα το πρωί για την υπόθεση.
me píre énas dhikighóros símera to proí ya tin ipóthesi
A lawyer called me this morning about the case.
Με πήρε κάποιος δικηγόρος, δεν θυμάμαι το όνομά του.
me píre kápios dhikighóros, dhen thimáme to ónomá tu
Some lawyer called me — I don't remember his name.
κάτι: invariable, and much more than "something"
κάτι never changes shape, in any gender, number or case. Its core meaning is something / anything:
Θέλεις κάτι από το σούπερ μάρκετ; Κατεβαίνω τώρα.
thélis káti apó to súper márket; katevéno tóra
Do you want anything from the supermarket? I'm going down now.
Beyond that, κάτι has a life English does not prepare you for. Followed by a plural noun it works as a vague quantifier — "some ... , you know the sort". This is (informal), entirely normal in speech, and it usually carries an evaluative colour: mild dismissal, surprise, or a shared understanding that the speaker cannot be bothered to specify.
Ήρθαν κάτι παιδιά και ρωτούσαν για σένα.
írthan káti pedhiá ke rotúsan ya séna
Some kids came round asking after you.
Έχει κάτι περίεργα πράγματα στο ψυγείο, μην τα φας.
échi káti períergha prághmata sto psiyío, min ta fas
There's some weird stuff in the fridge — don't eat it.
Note that this is not a sloppy substitute for μερικοί: swapping in μερικά παιδιά would give a neutral count ("a few children"), while κάτι παιδιά conveys "some kids or other, no idea who". Two more everyday uses are worth memorising as chunks: κάτι τέτοιο ("something like that") and κάτι after a round number for English -odd.
Δεν είπε ακριβώς αυτό, αλλά κάτι τέτοιο.
dhen ípe akrivós aftó, alá káti tétio
That's not exactly what he said, but something like that.
Είναι τριάντα κάτι χρονών, δεν ξέρω ακριβώς.
íne triánda káti chronón, dhen kséro akrivós
He's thirty-something — I don't know exactly.
In questions and negatives, the words change
This is where English speakers come unstuck, because English keeps some/any and simply adds not. Greek swaps the word itself: under negation, κάτι → τίποτα and κάποιος → κανένας. The negative forms are compulsory, and they come with an obligatory δεν — the negative concord described on κανένας.
| Thing | Person | |
|---|---|---|
| Statement | Είδα κάτι. | Ήρθε κάποιος. |
| Question | Είδες κάτι; / Είδες τίποτα; | Ήρθε κανείς; |
| Negation | Δεν είδα τίποτα. | Δεν ήρθε κανείς. |
In questions both series are available and the choice is one of expectation, not grammar. Είδες κάτι; leans towards "you did see something, didn't you?"; Είδες τίποτα; is open, and slightly more colloquial — both are correct Greek, and the second is what you will hear most in casual speech.
Άκουσες τίποτα από τη δουλειά που έκανες αίτηση;
ákuses típota apó ti dhuliá pu ékanes étisi;
Have you heard anything about the job you applied for?
There is one narrow context where κάποιος does survive under negation: when it is specific and contrastive rather than a plain existential. Δεν ψάχνω κάποιον συγκεκριμένο ("I'm not looking for anyone in particular") is good Greek, because the negation targets συγκεκριμένο, not the existence of the person. For the ordinary "nobody / nothing" meaning, though, κανένας and τίποτα are the only options.
Common Mistakes
1. Using μερικός in the singular for "some". μερικοί is plural-only in that sense; the singular μερικός means "partial".
❌ Μου το είπε μερικός συνάδελφος στη δουλειά.
Incorrect — for one unnamed person use κάποιος: κάποιος συνάδελφος.
✅ Μου το είπε κάποιος συνάδελφος, αλλά δεν ξέρω αν είναι αλήθεια.
mu to ípe kápios sinádhelfos, alá dhen kséro an íne alíthia
Some colleague told me, but I don't know whether it's true.
2. Putting μερικοί in front of a mass noun. Mass nouns take λίγο, or no quantifier at all.
❌ Έβαλα μερικό γάλα στον καφέ μου.
Incorrect — a mass noun cannot take μερικός; use λίγο γάλα.
✅ Έβαλα λίγο γάλα στον καφέ, δεν τον πίνω σκέτο.
évala lígho ghála ston kafé, dhen ton píno skéto
I put a little milk in the coffee — I don't drink it black.
3. Leaving κάποιος uninflected after a preposition. Every preposition takes the accusative, so it is κάποιον.
❌ Το είπα σε κάποιος φίλος μου.
Incorrect — after σε the accusative is required: σε κάποιον φίλο μου.
✅ Το είπα σε κάποιον φίλο μου και μου είπε να μη δώσω σημασία.
to ípa se kápion fílo mu ke mu ípe na mi dhóso simasía
I told a friend of mine and he told me not to pay it any attention.
4. Keeping κάποιος under a negation. "Nobody came" is not δεν … κάποιος.
❌ Δεν ήρθε κάποιος στην παρουσίαση.
Incorrect for 'nobody came' — plain negation requires κανένας: Δεν ήρθε κανείς.
✅ Δεν ήρθε κανείς στην παρουσίαση, μόνο ο διοργανωτής.
dhen írthe kanís stin parusíasi, móno o dhiorghanotís
Nobody came to the presentation — only the organiser.
5. Keeping κάτι under a negation. English I don't want something is behind this; Greek needs τίποτα.
❌ Δεν θέλω κάτι, ευχαριστώ.
Incorrect — under negation κάτι becomes τίποτα: Δεν θέλω τίποτα.
✅ Δεν θέλω τίποτα, έφαγα πριν έρθω.
dhen thélo típota, éfagha prin értho
I don't want anything — I ate before I came.
Key Takeaways
- Greek has no plural indefinite article, so μερικοί, κάποιοι and κάτι are what fill the "some + plural noun" slot.
- μερικοί / μερικές / μερικά = some, a few, plural only, with a bare noun. The singular μερικός is a different word meaning partial (μερική απασχόληση).
- κάποιος declines fully and singles out one unidentified referent — some man or other; the plural κάποιοι is certain people, more pointed than the neutral μερικοί.
- ένας introduces a referent the speaker has in mind; κάποιος says the identity is unknown or irrelevant.
- κάτι is invariable. Beyond something, it works before a plural noun as a colloquial vague quantifier (κάτι παιδιά) and in the chunks κάτι τέτοιο and τριάντα κάτι.
- Under negation the words change: κάτι → τίποτα, κάποιος → κανένας, both with an obligatory δεν. In questions, κάτι and τίποτα are both correct, with τίποτα the more colloquial and more open of the two.
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Start learning Greek →Related Topics
- Quantifiers: πολύς, λίγος, αρκετόςA2 — Greek's graded quantifiers — πολύς (much/many), λίγος (little/few), αρκετός (enough and 'quite a lot'), plus informal κάμποσος — all of which agree with their noun, so that a single word covers both English 'much' and 'many': πολύ νερό but πολλά παιδιά, λίγη ζέστη but λίγες μέρες. Includes the question word πόσος and the zero-quantity καθόλου.
- κανένας: 'no/any' and NegationA2 — κανένας / καμιά / κανένα is Greek's 'nobody' and its 'any' in one word, and it never works alone: Δεν ήρθε κανείς needs both δεν and κανείς, because Greek stacks negatives instead of cancelling them. Full paradigm, the κανείς/κανένας doublet, the obligatory δεν even in Κανείς δεν ήρθε, and the friendly spoken reading in Πάμε για κανένα ποτό;
- Indefinite PronounsB1 — A map of Greek's indefinite pronouns rather than a lesson on any one of them: κάποιος, κάτι, μερικοί, καθένας, κανένας, τίποτα and the -δήποτε words sorted by two questions — does it inflect, and which of the three series does it belong to. Every word here has a page of its own; this one tells you which page you need, and covers the free-choice series οποιοσδήποτε / οτιδήποτε in full.
- κάτι vs κάποιοςB1 — Not the forms — the choice. κάποιος points at a person the speaker could name and will not; κάτι points at a thing or, far more often, an event the speaker cannot name at all, which is why Κάτι έγινε and Κάτι τρέχει have no κάποιος counterpart. Plus the neuter-singular agreement that κάτι forces on everything after it (κάτι καινούριο, κάτι το γοητευτικό) and the narrow escape hatch that lets both words survive a negation.