Masculine nouns ending in -ας split into two families that look identical in the nominative singular but form their plural in completely different ways. Getting the plural right means recognising which family a noun belongs to — and there is no way to tell from the singular alone. This page lays out both patterns and the one small trap that catches almost every learner: the genitive singular ends in a bare -α, with no -ς.
Family one: parisyllabic (same syllable count)
The larger group is parisyllabic (Greek ισοσύλλαβα) — the singular and plural have the same number of syllables. These are everyday nouns like ο άντρας (the man), ο πατέρας (the father), ο μήνας (the month), ο χειμώνας (the winter), ο κανόνας (the rule).
Here is ο άντρας in full:
| Case | Singular | Plural |
|---|---|---|
| Nominative | ο άντρας | οι άντρες |
| Genitive | του άντρα | των αντρών (shift →) |
| Accusative | τον άντρα | τους άντρες |
| Vocative | άντρα | άντρες |
The endings for the parisyllabic type are -ας / -α / -α / -α in the singular and -ες / -ων / -ες / -ες in the plural. Notice that three of the four singular forms (genitive, accusative, vocative) are the same bare -α — a real economy compared with the -ος class.
Ένας άντρας ρωτούσε για σένα στη ρεσεψιόν.
énas ándras rotúse ya séna sti resepsión
A man was asking for you at reception.
Το παλτό του άντρα ξεχάστηκε στην καρέκλα.
to paltó tu ándra ksechástike stin karékla
The man's coat was left on the chair.
Οι άντρες της ομάδας προπονούνται κάθε πρωί.
i ándres tis omádhas proponúnde káthe proí
The men on the team train every morning.
ο πατέρας works the same way — and notice the genitive singular του πατέρα, again with no -ς:
Πήγα να πάρω τον πατέρα μου από το αεροδρόμιο.
pígha na páro ton patéra mu apó to aerodhrómio
I went to pick my father up from the airport.
Το αυτοκίνητο του πατέρα μου είναι παλιό αλλά αξιόπιστο.
to aftokínito tu patéra mu íne palió alá aksiópisto
My father's car is old but reliable.
The genitive plural accent is lexical — flag it, don't guess
One honest complication: for parisyllabic -ας nouns stressed on the next-to-last syllable, the genitive plural accent is not predictable. Some nouns pull the accent onto the ending (των αντρών, των μηνών), while others keep it where the nominative had it (των πατέρων, των χειμώνων). There is no clean rule; it is a lexical property you learn per word. The good news is that the genitive plural of these nouns is relatively rare in everyday speech, so you meet the forms one at a time.
Ο μήνας Αύγουστος είναι ο πιο ζεστός εδώ.
o mínas ávghustos íne o pio zestós edhó
The month of August is the hottest here.
Τα ρούχα των αντρών είναι στον δεύτερο όροφο.
ta rúcha ton andrón íne ston dhéftero órofo
The men's clothing is on the second floor.
The proparoxytone subgroup: the shift you can't avoid
There is one corner of the -ας class where the genitive plural accent is not a matter of luck: the proparoxytone nouns, stressed three syllables from the end. ο πρίγκιπας (prince), ο πρόσφυγας (refugee), ο φύλακας (guard, museum attendant), ο κόρακας (crow), ο χάρακας (ruler). Every one of them moves the stress one syllable to the right in the genitive plural:
- ο πρίγκιπας → των πριγκίπων
- ο πρόσφυγας → των προσφύγων
- ο φύλακας → των φυλάκων
- ο κόρακας → των κοράκων
This is not a whim. Greek never stresses further back than the third syllable from the end, and the genitive plural ending -ων is inherited as a long syllable, which pulls the permitted window forward: with -ων in place, the earliest the accent may sit is the next-to-last syllable. Hence ×των πρόσφυγων is impossible, and των προσφύγων is the only legal output.
The crucial detail — and the point where the -ας class parts company with the -ος class — is that this affects only the genitive plural. The accusative plural ending -ες is short, so nothing moves: τους πρόσφυγες, τους φύλακες. Compare ο άνθρωπος, where the accusative plural -ους is long and therefore does drag the accent: τους ανθρώπους.
Ο φύλακας του μουσείου μάς είπε ότι κλείνει σε δέκα λεπτά.
o fílakas tu musíu mas ípe óti klíni se dhéka leptá
The museum attendant told us it closes in ten minutes.
Οι πρόσφυγες περίμεναν ώρες στην ουρά για χαρτιά.
i prósfiyes perímenan óres stin urá ya chartiá
The refugees waited for hours in line for paperwork.
Η άφιξη των προσφύγων άλλαξε τη ζωή του νησιού.
i áfiksi ton prosfíghon álakse ti zoí tu nisiú
The arrival of the refugees changed life on the island.
Family two: imparisyllabic (an extra syllable in the plural)
The second group is imparisyllabic (Greek ανισοσύλλαβα) — the plural gains a whole extra syllable, inserting -δ- and ending in -άδες. These are overwhelmingly occupational or agent nouns, and they are oxytone (stressed on the last syllable): ο ψαράς (the fisherman) and ο παπάς (the priest) are the clearest members, so we will build the paradigm on those.
| Case | Singular | Plural |
|---|---|---|
| Nominative | ο ψαράς | οι ψαράδες |
| Genitive | του ψαρά | των ψαράδων |
| Accusative | τον ψαρά | τους ψαράδες |
| Vocative | ψαρά | ψαράδες |
The singular endings are the same bare -άς / -ά / -ά / -ά as the parisyllabic type — the split only shows in the plural: -άδες / -άδων / -άδες / -άδες. Because these nouns are oxytone, the stress stays on that same vowel throughout; it never shifts.
Ο ψαράς πουλάει φρέσκα ψάρια κάθε Παρασκευή.
o psarás pulái fréska psária káthe paraskeví
The fisherman sells fresh fish every Friday.
Οι ψαράδες γύρισαν στο λιμάνι πριν την καταιγίδα.
i psarádhes yírisan sto limáni prin tin kateyídha
The fishermen returned to the harbour before the storm.
Ο παπάς του χωριού ξέρει τα πάντα για όλους.
o papás tu choriú kséri ta pánda ya ólus
The village priest knows everything about everyone.
The trap: genitive singular has no -ς
Here is the error to watch above all others. In every -ας noun, the genitive singular ends in a bare -α — the -ς of the nominative disappears. Learners keep the -ς by force of habit, because the dictionary form ends in it:
- ο άντρας → του άντρα (not ×του άντρας)
- ο πατέρας → του πατέρα (not ×του πατέρας)
- ο ψαράς → του ψαρά (not ×του ψαράς)
The logic is the same one you met in the -ος class: the final -ς is purely a nominative singular marker. It is stripped off in the genitive, the accusative, and the vocative. Say it to yourself as a slogan: the -ς lives only in the nominative.
Η γνώμη του πατέρα μετράει πολύ για μένα.
i ghnómi tu patéra metrái polí ya ména
My father's opinion means a lot to me.
Common Mistakes
1. Keeping the -ς in the genitive singular. This is the signature -ας error.
❌ Το αμάξι του άντρας είναι μαύρο.
Incorrect — the genitive drops the -ς: του άντρα.
✅ Το αμάξι του άντρα είναι μαύρο.
to amáksi tu ándra íne mávro
The man's car is black.
2. Giving a parisyllabic noun the -άδες plural. ο άντρας is parisyllabic — its plural is άντρες, never ×αντράδες.
❌ Οι αντράδες περίμεναν έξω.
Incorrect — άντρας is parisyllabic: the plural is άντρες.
✅ Οι άντρες περίμεναν έξω.
i ándres perímenan ékso
The men were waiting outside.
3. Giving an imparisyllabic noun the plain -ες plural. ο ψαράς takes -άδες, never ×ψαρές.
❌ Οι ψαρές έφυγαν νωρίς το πρωί.
Incorrect — ψαράς is imparisyllabic: the plural is ψαράδες.
✅ Οι ψαράδες έφυγαν νωρίς το πρωί.
i psarádhes éfighan norís to proí
The fishermen left early in the morning.
4. Using the nominative to address someone. The vocative of -ας nouns is the bare -α.
❌ Κώστας, έλα να φας!
Incorrect — the vocative is Κώστα, not Κώστας.
✅ Κώστα, έλα να φας!
kósta, éla na fas!
Kostas, come and eat!
Key Takeaways
- Masculine -ας nouns come in two families with the same-looking singular but different plurals.
- Parisyllabic (ο άντρας, ο πατέρας, ο μήνας): plural in -ες (άντρες), same syllable count.
- Imparisyllabic (ο ψαράς, ο παπάς): plural in -άδες (ψαράδες), one extra syllable; typically job/agent nouns and oxytone.
- The genitive singular is a bare -α in both families — the -ς is dropped (του άντρα, του ψαρά). This is the most common -ας mistake.
- The genitive plural accent of paroxytone parisyllabic nouns is lexical (των αντρών but των πατέρων) — learn it per word. Proparoxytone nouns are the predictable ones: the accent must move (των προσφύγων, των πριγκίπων), but only in the genitive plural (τους πρόσφυγες, not ×τους προσφύγες).
- A third, contracted type is next door: ο καφές, ο παππούς — plural in -δες like ο ψαράς, but genitive singular του καφέ, του παππού.
- The vocative singular is also the bare -α (Κώστα!).
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Start learning Greek →Related Topics
- Imparisyllabic Masculines (-άδες, -ούδες)B1 — A large family of masculine nouns — ο ψαράς, ο καφές, ο παππούς, ο μπακάλης — that grows an extra syllable in the plural (οι ψαράδες, οι καφέδες), a pattern English has almost nowhere.
- Masculine Nouns in -ης and -εςA2 — Masculine agent and family nouns like ο μαθητής, ο ναύτης and ο πολίτης — singular in -ης, plural in -ες, with an oxytone genitive plural in -ών, the -η vocative, the rival -ηδες plural of surnames and trade words, and a warning not to confuse this noun ending with the -ης two-termination adjective.
- Contracted Masculines: ο καφές, ο παππούς, ο νουςB1 — The contracted singular of ο καφές, ο παππούς, ο μπαμπάς and ο νους — nouns whose genitive, accusative and vocative are nothing but a bare stressed vowel (του καφέ, του παππού, του νου), so the article alone carries the case.
- The Genitive Plural (-ων)B1 — The plural 'of the…' form ends in -ων for almost every Greek noun (των ανθρώπων, των παιδιών, των πόλεων→-εων), and the article is always των — but the stress is the trickiest in the language, so natives often sidestep the awkward ones with από + accusative.