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Re: At end of a word is it ος or ου?
by Greg Brush - Wednesday, 11 January 2023, 02:22 PM
  I don't understand your question. If you are pronouncing words ending in -ος or -ο as -ου, then you are either mispronouncing the word(s) or you are misunderstanding when to use a particular inflectional form.

Words ending in -ος are mostly masculine nominative singulars, along with a relatively few feminines like η Πάφος (L46) and neuters like το μέρος (L15).
Words ending in -ο are neuter nominative/accusative singulars, along with the accusative singular of masculine & feminine nouns ending -ος.

Because of word inflection (changes in endings to indicate grammatical function), such masculine and feminine words DO end in -ου in the genitive singular (the neuter genitive ends in -ους).
For example:
ο φίλος (L16), τον φίλο, του φίλου
ο Ιάκωβος, τον Ιάκωβο, του Ιακώβου
η Πάφος, την Πάφο, της Πάφου
το μέρος, του μέρους

So the Greek version of "Paphos is a city on Cyprus" is η Πάφος [nominative] είναι πόλη στην Κύπρο,
while "I used to live in Paphos" is Έμενα στην Πάφο [accusative],
and a guidebook titled "A Paphos Guide" is Οδηγός της Πάφου [genitive].

Hope this helps,
Greg Brush