Modern Greek keeps many doubled consonants in its spelling — θάλασσα, γράμμα, άλλος, Ελλάδα — but it pronounces every one of them as a single sound. As the pronunciation page explains, θάλασσα is said thálasa, with one short [s]. The consequence for writing is brutal: your ear cannot help you at all. Since θάλασσα and a non-existent ×θάλασα would sound identical, the only way to spell these words correctly is to know which words take a double. There is no sound-based rule. But there are patterns and word-families that shrink the memory load, and that is what this page delivers.
Why this has to be memorized
Let us be honest about the difficulty up front: this is one of the few areas of Greek spelling with no phonetic shortcut whatsoever. With ω/ο or η/ι you can at least lean on grammar (a genitive plural is -ων, a 1sg verb is -ω). With doubles, there is nothing to lean on — the doubling is a pure fossil of the word's history. Even educated native speakers hesitate on the rarer ones, and a few (like συγγνώμη) are among the most commonly misspelled words in the language. So the honest strategy is: learn the frequent doubled words as fixed shapes, learn the handful of patterns that generate them, and accept that the long tail is memorization.
The frequent culprits
Some doubled letters are far more common than others. In rough order of how often you will meet them: σσ, λλ, μμ, ρρ, νν, ππ, ττ, ββ, κκ. Here are the highest-frequency words in each — learn these first, because they carry most of your everyday writing.
| Double | High-frequency words |
|---|---|
| σσ | θάλασσα (sea), γλώσσα (tongue/language), τέσσερα (four), περισσότερο (more), μέλισσα (bee) |
| λλ | άλλος (other), Ελλάδα (Greece), Έλληνας (Greek), μάλλον (probably), αλλάζω (change) |
| μμ | γράμμα (letter), γραμμή (line), γραμματική (grammar), κομμάτι (piece), πρόγραμμα (programme) |
| ρρ | θάρρος (courage), άρρωστος (ill), αρραβώνας (engagement) |
| νν | Άννα, Γιάννης, εννιά (nine), γέννηση (birth), σύννεφο (cloud) |
| ππ | ίππος (horse), Φίλιππος (Philip), ιππότης (knight), ιπποπόταμος (hippo) |
| ττ | Αττική (Attica) — ττ is rare in everyday words |
| ββ | Σάββατο (Saturday), αββάς (abbot) |
| κκ | εκκλησία (church), κόκκινος (red) |
Το καλοκαίρι πάμε κάθε μέρα στη θάλασσα.
to kalokéri páme káthe méra sti thálasa.
In summer we go to the sea every day.
Η ελληνική γραμματική έχει πολλούς κανόνες.
i elinikí ghramatikí échi polús kanónes.
Greek grammar has many rules.
Θέλω τέσσερα εισιτήρια, όχι περισσότερα.
thélo tésera isitíria, óchi perisótera.
I want four tickets, no more.
Μάλλον θα βρέξει αύριο το απόγευμα.
málon tha vréksi ávrio to apóyevma.
It'll probably rain tomorrow afternoon.
A note on ττ: many words that had ττ in ancient/learned Greek use single τ in the modern demotic standard — the cat is γάτα (single τ), "four" is τέσσερα (with σσ, not the older ττ of τέτταρα). Do not over-supply ττ.
Word families keep the doubling
Here is the pattern that gives the most return for the least effort: a doubled consonant is inherited by the whole word-family. Learn the doubling once in the base word and it carries into every derivative.
- θάλασσα (sea) → θαλασσινός (of the sea), θαλάσσιος (marine), θαλασσί (sea-blue)
- γράμμα (letter) → γραμματική (grammar), γραμματέας (secretary), γράμματα (letters/learning)
- Ελλάδα (Greece) → Έλληνας (Greek man), Ελληνίδα (Greek woman), ελληνικά (Greek language)
- γλώσσα (language) → γλωσσικός (linguistic), γλωσσολογία (linguistics)
Μου αρέσουν πολύ τα φρέσκα θαλασσινά.
mu arésun polí ta fréska thalasiná.
I really like fresh seafood.
Ο Γιάννης είναι Έλληνας από τη Θεσσαλονίκη.
o yánis íne élinas apó ti thesaloníki.
Giannis is a Greek from Thessaloniki.
Loanwords simplify the double
Words borrowed into Modern Greek generally drop the gemination that the source language wrote. This is a useful default in reverse: if a word is a recent international loan, assume a single consonant unless you know otherwise.
- tennis → τένις (single ν), train → τρένο (single, from Italian treno), garage → γκαράζ, ballet → μπαλέτο (single λ)
Το τρένο για την Αθήνα φεύγει στις οκτώ.
to tréno ya tin athína févyi stis októ.
The train to Athens leaves at eight.
Παίζει τένις κάθε Σάββατο το πρωί.
pézi ténis káthe sávato to proí.
He plays tennis every Saturday morning.
Notice Σάββατο in that last sentence keeps its inherited ββ (it is an old, native word), while the loanword τένις does not double. Age and origin, not sound, decide.
Prefixes create doubles at the seam
A smaller but tidy pattern: when a prefix ending in a consonant meets a root beginning with the same or an assimilating consonant, a double appears at the join. The prefix συν- ("with, together") is the great generator:
- συν + νέφος → σύννεφο (cloud) — νν
- συν + λαβή → συλλαβή (syllable), συν + λογή → συλλογή (collection) — λλ
- συν + μαθητής → συμμαθητής (classmate), συν + μετοχή → συμμετοχή (participation) — μμ
- συν + ράπτω → συρραφή (stitching) — ρρ
And συγγνώμη ("sorry, excuse me") comes from συν + γνώμη, producing γγ — one of the most frequently misspelled words in Greek, constantly written ×συγνώμη even by natives.
Ο ουρανός είναι γεμάτος γκρίζα σύννεφα σήμερα.
o uranós íne yemátos gríza sínefa símera.
The sky is full of grey clouds today.
Συγγνώμη, δεν σε άκουσα καλά.
sighnómi, dhen se ákusa kalá.
Sorry, I didn't hear you well.
Common Mistakes
1. Dropping a letter because you can't hear it. θάλασσα takes σσ even though only one [s] is said.
❌ Η θάλασα ήταν κρύα σήμερα.
Wrong — 'sea' is θάλασσα with σσ; the single [s] you hear never tells you.
✅ Η θάλασσα ήταν κρύα σήμερα.
i thálasa ítan kría símera.
The sea was cold today.
2. Simplifying Ελλάδα. Greece and its whole family keep λλ.
❌ Μένω στην Ελάδα εδώ και δέκα χρόνια.
Wrong — Greece is Ελλάδα with λλ, and so is Έλληνας, ελληνικά.
✅ Μένω στην Ελλάδα εδώ και δέκα χρόνια.
méno stin eládha edhó ke dhéka chrónia.
I've been living in Greece for ten years.
3. Writing συγγνώμη without the γγ. It comes from συν + γνώμη.
❌ Συγνώμη για την καθυστέρηση.
Wrong — 'sorry' is συγγνώμη with γγ (from συν- + γνώμη), even though natives often slip.
✅ Συγγνώμη για την καθυστέρηση.
sighnómi ya tin kathistérisi.
Sorry for the delay.
4. Simplifying γραμματική. It keeps μμ from its family word γράμμα.
❌ Η ελληνική γραματική είναι δύσκολη.
Wrong — γραμματική takes μμ (family of γράμμα).
✅ Η ελληνική γραμματική είναι δύσκολη.
i elinikí ghramatikí íne dhískoli.
Greek grammar is hard.
5. Over-doubling a loanword. Borrowings simplify — "tennis" is τένις with a single ν.
❌ Παίζω τέννις τρεις φορές τη βδομάδα.
Wrong — the loanword 'tennis' is written τένις with a single ν.
✅ Παίζω τένις τρεις φορές τη βδομάδα.
pézo ténis tris forés ti vdhomádha.
I play tennis three times a week.
Key Takeaways
- There is no phonetic rule for doubles — Greek says a single sound, so you must know the word. This is pure spelling memory.
- Learn the high-frequency doubled words first: θάλασσα, γλώσσα, τέσσερα, περισσότερο (σσ); άλλος, Ελλάδα, μάλλον (λλ); γράμμα, γραμματική, κομμάτι (μμ).
- Word families keep the doubling: θάλασσα → θαλασσινός, γράμμα → γραμματική, Ελλάδα → Έλληνας. Learn it once, apply it across the family.
- Loanwords simplify (τένις, τρένο); prefix seams create doubles (συν → σύννεφο, συλλαβή, συμμετοχή, and the tricky συγγνώμη).
Now practice Greek
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Start learning Greek→Related Topics
- Double ConsonantsA2 — θάλασσα is said 'thálasa', άλλος is 'álos', Ελλάδα is 'Eládha' — Modern Greek pronounces a double consonant as a single sound. You must spell the two letters but say only one.
- Spelling Verb EndingsB1 — A verb ending is spelled by what it does, not by how it sounds. Learn the fixed spellings — active -ω, -εις, -ει; passive -ομαι, -εται — and the three homophone traps they resolve, like γράφεται (is written) vs γράφετε (you write).
- Spelling Diminutive SuffixesB1 — Greek loves little-word suffixes — σπιτάκι, μανούλα, κοπελίτσα — and each has a fixed spelling learners get wrong: -άκι with iota (and it's neuter), -ούλα with ου, -ίτσα with τσ, plus the stress that always lands on the suffix.