-ας

-ᾱς • (-ās)

1. The nominative singular ending of masculine first-declension nouns in most dialects. Replaced by -ης (-ēs) in all cases in Ionic, and in most cases in Attic.
2. The genitive singular ending of feminine first-declension nouns and adjectives in many dialects. Replaced by -ης (-ēs) in all cases in Ionic, and in most cases in Attic.
3. The accusative plural ending of all first-declension nouns and adjectives in many dialects. -ᾰς (-as) or -ᾰνς (-ans), -αις (-ais), and -αιρ (-air) are used by dialects attested from inscriptions.

-ᾰς • (-as)

1. The accusative plural ending of most third-declension nouns and many third-declension adjectives. -ᾰνς (-ans) is also used in the Cretan dialect.
2. The accusative plural ending of first-declension nouns and adjectives in various dialects attested in inscriptions: see Appendix:Ancient Greek dialectal declension § First declension.

Metanalysis of *-sants, a combination of the typical suffix of the first aorist active stem *-sa and *-nts (from Proto-Indo-European *-onts). Several other participial formations also descend from a form in *-nts: the present active -ων (-ōn), the second aorist active in -ών (-ṓn), the contracted present active and contracted future active in -ῶν (-ôn), the aorist passive in -είς (-eís), and several present active and aorist active athematic forms like ἱστᾱ́ς (histā́s) and στᾱ́ς (stā́s).

-ας • (-as) m (feminine -ᾱσᾰ, neuter -ᾰν); first/third declension

1. first aorist active participle ending

   ‎δειξ- (deix-, first aorist stem of δείκνῡμι (deíknūmi)) + ‎-ας (-as) → ‎δείξᾱς (deíxās)

   ‎λῡσ- (lūs-, first aorist stem of λῡ́ω (lū́ō)) + ‎-ας (-as) → ‎λῡ́σᾱς (lū́sās)

   ‎μειν- (mein-, first aorist stem of μένω (ménō)) + ‎-ας (-as) → ‎μείνᾱς (meínās)