Feminine -ος Nouns (η οδός)
A handful of very common nouns END in -ος yet are FEMININE: η οδός (“the street/avenue”), η μέθοδος (“the method”), η είσοδος (“the entrance”), η έξοδος (“the exit”), η νόσος (“the disease”). They are a survival of the ancient second-declension feminine. The surprise is only the gender: they DECLINE with the ordinary -ος endings you already know from δάσκαλος - acc sg -ο (την οδό), gen sg -ου (της οδού), plural nom -οι (οι οδοί), acc -ους (τις οδούς), gen -ων (των οδών). What carries the feminine is the ARTICLE: η / την / της in the singular, οι / τις / των in the plural. So η οδός takes a feminine article on an -ος body - always pair these nouns with η, never ο. Stress behaves exactly as for masculine -ος: oxytone οδός never shifts (οδών), but antepenult-stressed μέθοδος pulls the stress to the penult in the oblique cases (της μεθόδου, των μεθόδων), just like άνθρωπος → ανθρώπων.
The rule
A small, high-frequency class of nouns ends in -ος yet is FEMININE - a survival of the ancient second declension: η οδός (“street/avenue”), η μέθοδος (“method”), η είσοδος (“entrance”), η έξοδος (“exit”). They decline with the ordinary -ος endings (acc sg -ο την οδό, gen sg -ου της οδού, pl nom -οι οι οδοί, acc -ους τις οδούς, gen -ων των οδών); the feminine article - η / την / της · οι / τις / των - is the only gender signal. Stress works exactly as for masculine -ος: oxytone οδός never shifts (οδών), but antepenult-stressed μέθοδος pulls the stress to the penult in the oblique cases (της μεθόδου*, των μεθόδων), like άνθρωπος → ανθρώπου / ανθρώπων. Store each as article + noun (η μέθοδος) so the feminine article is never in doubt - and it is monotonic (της οδού, never the polytonic τῆς ὁδοῦ*).
Paradigm
| Case | Singular | Plural |
|---|---|---|
| Nominative | οδός | οδοί |
| Accusative | οδό | οδούς |
| Genitive | οδού | οδών |
| Vocative | — | — |
| Case | Singular | Plural |
|---|---|---|
| Nominative | μέθοδος | μέθοδοι |
| Accusative | μέθοδο | μεθόδους† |
| Genitive | μεθόδου† | μεθόδων† |
| Vocative | — | — |
- The stress moves to the penult (-όδους) in the accusative plural (μέθοδος → μεθόδους).
- Antepenult-stressed -ος: the stress moves to the penult (-όδου) in the genitive singular (μέθοδος → μεθόδου).
- The stress moves to the penult (-όδων) in the genitive plural (μέθοδος → μεθόδων).