τρῐᾱκοντα-έτης,
Ionic dialect τρῐηκ-, ες, thirty years old, [[ 5th-6th c.BC: Plato Philosophus “Leges” 914b, 961b (in the former place without a variant, in the latter codices AO have τριακοντ᾽ ἔτη), “PAmh.” 2.84.12 (2nd-3rd c.AD), “Riv.Fil.” 57.379 (Aptera, 3rd-4th c.AD)] Refs 5th c.BC+]; also in forms τριᾱκοντέτης (which see) and τριᾱκοντούτης, ου, ὁ, accusative plural τοὺς τριακοντούτας the men of thirty years, [[ 5th-6th c.BC: Plato Philosophus “Respublica” 539a, “Lg.” 670a] Refs 5th c.BC+]; nominative singular masculine -ούτης [[2nd c.AD: Galenus Medicus 6.471 ] Refs 2nd c.AD+]; feminine τριακοντοῦτις, [[ 4th c.BC: Isaeus Orator 6.14, “CRAcad.Inscription” 1932.85 (Tipasa in Mauretania). ] Refs 4th c.BC+]
__II of or for thirty years, τριακονταέτεις σπονδαί [[ 5th c.BC: Thucydides Historicus 5.14, 5th-6th c.BC: Xenophon Historicus “Historia Graeca (Hellenica)” 5.2.2; αἱ τριακοντούτεις σπονδαί 5th c.BC: Thucydides Historicus 1.23, 115, 2.2 (whence 5.14 and 5th-6th c.BC: Xenophon Historicus [prev. cited] have been corrected): in _feminine_ form, σπονδὰς τριηκοντοέτιδας (variant{-ταέτιδας}) 5th c.BC: Herodotus Historicus 7.149; σπονδαὶ τριακοντούτιδες 5th-6th c.BC: Aristophanes Comicus “Acharnenses” 194, compare “Eq.” 1388, 5th c.BC: Thucydides Historicus 1.87 ] Refs 5th c.BC+] (though elsewhere he uses the form in νς as feminine, see above).