τρεῖς, οἱ, αἱ, τρία, τά:
genitive τριῶν: dative τρισί, also τριοῖσι [[ 6th c.BC: Hipponax Iambographus 51, and τρίεσσι “Delph.” 3(5).80.21 (4th c.BC)] Refs 6th c.BC+]; Aeolic dialect τρίσσι [[ “Inscription Perg.” 245 B 18 (from Pitana): _accusative_ τρεῖς] Refs] (written τρες [[ “IG” 12.24.16, 44.15, 188.37, 1085, +others), τρία] Refs]: Doric dialect nominative τρέες [[ “Leg.Gort.” 9.48; τρῆς “IG” 12(3).1640 (from Thera)] Refs]; τρῖς [[ “SIG” 236 A 10 (Delph., 4th c.BC), “Tab.Heracl.” 1.23; _accusative_ τρίινς “Leg.Gort.” 5.54, +others (for Τρίνς, lengthened to correspond with the other cases)] Refs 4th c.BC+]; τρῖς [[ “IG” 12.838,839 (6th c.BC), “SIG” 239 D ii 28 (Delph., 4th c.BC), “Berl.Sitzb.” 1927.158 (from Cyrene)] Refs 6th c.BC+]:—three, [[ 8th c.BC: Ilias Homerus Epicus “Illiad” 15.187, etc.] Refs 8th c.BC+]; τρία ἔπεα three words, proverbial in [[ 5th c.BC: Pindarus Lyricus “N.” 7.48,] Refs 5th c.BC+]—for from the earliest times three was a sacred and lucky number, especially with the Pythagoreans (compare τριάς), [[ 4th c.BC: Aristoteles Philosophus “de Caelo” 268a11; so τῶν τριῶν μίαν λαβεῖν εὔσοιαν 5th c.BC: Sophocles Tragicus “Fragmenta” 122 ] Refs 5th c.BC+]; εἰ καὶ τῶν τριῶν ἓν οἴσομαι[[ [prev. work] 908; compare σωτήρ 1.2:] Refs] —διὰ τριῶν ἀπόλλυμαι I am thrice, i. e. utterly, undone, [[ 5th c.BC: Euripides Tragicus “Orestes” 434 (compare τριάζω)] Refs 5th c.BC+]; ἡ διὰ τριῶν ἀγωγή the 'trivium', [[ 6th c.AD: Simplicius Philosophus “in Aristotelis Physica commentaria - Comm. in Arist. Graeca” 1171.34; ἵνα δήσῃ τρία τρία ] Refs 6th c.AD+]by threes, [[ POxy. 121.19 (3rd c.AD). (I.- 5th c.BC: Euripides Tragicus ] Refs 5th c.BC+] stem tr[icaron]-, fuller form trey-, nominative tréy-es (Sanskrit tráyas, Latin tres), whence τρέες, contraction τρῆς and τρεῖς (written τρες [[ “IG” 12.295.11)] Refs]; accusative tri-ns (Gothic prins, Sanskrit tr[imacracute]n), whence τρῖς and τρίιν; in Gr. the nominative τρεῖς functions as accusative (as in Attic dialect), or the accusative τρῖς as nominative ([same places]).)