The formation is similar to φρίξ (phríx). According to Beekes, possibly from Pre-Greek, like πνίγω (pnígō, “to choke, asphyxiate”).
πνῐ́ξ • (pníx) f (genitive πνῐγός); third declension
| Case / # | Singular | Dual | Plural | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominative | ἡ πνῐ́ξ hē pníx |
τὼ πνῐ́γε tṑ pníge |
αἱ πνῐ́γες hai pníges | ||||||||||
| Genitive | τῆς πνῐγός tês pnigós |
τοῖν πνῐγοῖν toîn pnigoîn |
τῶν πνῐγῶν tôn pnigôn | ||||||||||
| Dative | τῇ πνῐγῐ́ têi pnigí |
τοῖν πνῐγοῖν toîn pnigoîn |
ταῖς πνῐξῐ́ / πνῐξῐ́ν taîs pnixí(n) | ||||||||||
| Accusative | τὴν πνῐ́γᾰ tḕn pníga |
τὼ πνῐ́γε tṑ pníge |
τᾱ̀ς πνῐ́γᾰς tā̀s pnígas | ||||||||||
| Vocative | πνῐ́ξ pníx |
πνῐ́γε pníge |
πνῐ́γες pníges | ||||||||||
| Notes: |
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