τρία

τρες, τρες, τά
A. τριοῖσι Hippon. 51, and τρίεσσι Delph. 3(5).80.21 (iv B. C.); Aeol. τρίσσι Inscr.Perg. 245 B 18 (Pitana): acc. τρεῖς (written τρες IG 12.24.16, 44.15, 188.37, 1085, al.), τρία: Dor. nom. τρέες Leg.Gort. 9.48; τρῆς IG 12(3).1640 (Thera); τρῖς SIG 236 A 10 (Delph., iv B. C.), Tab.Heracl. 1.23; acc. τρίινς Leg.Gort. 5.54, al. (for Τρίνς, lengthd. to correspond with the other cases); τρῖς IG 12.838,839 (vi B. C.), SIG 239 D ii 28 (Delph., iv B. C.), Berl.Sitzb. 1927.158 (Cyrene):—three, Il. 15.187, etc.; τρία ἔπεα three words, prov. in Pi. N. 7.48,—for from the earliest times three was a sacred and lucky number, esp. with the Pythagoreans (cf. τριάς), Arist. Cael. 268a11; so τῶν τριῶν μίαν λαβεῖν εὔσοιαν S. Fr. 122; εἰ καὶ τῶν τριῶν ἓν οἴσομαι ib.908; cf. σωτήρ 1.2:—διὰ τριῶν ἀπόλλυμαι I am thrice, i. e. utterly, undone, E. Or. 434 (cf. τριάζω); ἡ διὰ τριῶν ἀγωγή the 'trivium', Simp. in Ph. 1171.34; ἵνα δήσῃ τρία τρία by threes, POxy. 121.19 (iii A. D.). (I.-E. stem tr[icaron]-, fuller form trey-, nom. tréy-es (Skt. tráyas, Lat. tres), whence τρέες, contr. τρῆς and τρεῖς (written τρες IG 12.295.11); acc. tri-ns (Goth. prins, Skt. tr[imacracute]n), whence τρῖς and τρίινς; in Gr. the nom. τρεῖς functions as acc. (as in Att.), or the acc. τρῖς as nom. (ll. cc.).)
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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