From Proto-Finnic *peikälo. The phonological development of this word is somewhat irregular: *peikälo → *peigäl (changes to an e-stem noun) → *pëigal (backing of *-e- after the knowledge of the original *-ä-'s existence lost) → *põial (intermediate form) → pöial, but also the original weak grade consonant was changed from -g- to -d-.
pöial (genitive pöidla, partitive pöialt)
| Declension of pöial (ÕS type 8/küünal, d-ø gradation) | |||
|---|---|---|---|
| singular | plural | ||
| nominative | pöial | pöidlad | |
| accusative | nom. | ||
| gen. | pöidla | ||
| genitive | pöialde | ||
| partitive | pöialt | pöidlaid | |
| illative | pöidlasse | pöialdesse pöidlaisse | |
| inessive | pöidlas | pöialdes pöidlais | |
| elative | pöidlast | pöialdest pöidlaist | |
| allative | pöidlale | pöialdele pöidlaile | |
| adessive | pöidlal | pöialdel pöidlail | |
| ablative | pöidlalt | pöialdelt pöidlailt | |
| translative | pöidlaks | pöialdeks pöidlaiks | |
| terminative | pöidlani | pöialdeni | |
| essive | pöidlana | pöialdena | |
| abessive | pöidlata | pöialdeta | |
| comitative | pöidlaga | pöialdega | |
pöial