ō

Ω, ὦ, τό,
twenty-fourth and last letter of the Ionic alphabet, ἀπὸ ἄλφα ἕως.ω. Refs 9th c.AD+; thence used as a symbol of the end, the last, ἐγώ εἰμι τὸ ἄλφα καὶ τὸ ὦ (not τὸ ὦ μέγα) NT:—as a numeral ώ = 800, but ωνυμ = 800, 000. The epichoric _Attic dialect_ and other alphabets of the Inscrr. had used o in differently to represent the sounds of the later ο and ω: Ω is a differentiated form of ο, and, though usually = ω, was used in the Ionic islands of Paros, Thasos, and Siphnos with the value ο, while O or O represented the sound ω. The name of the letter was τὸ ὦ (perispomenon accusative to Refs 5th c.BC+: after the loss of the distinction between long and short vowels, ο and ω had the same pronunciation; they begin to be confused in Papyri of Refs 3rd c.BC+(οἰκωνόμου Refs 3rd c.BC+, but the name ω μέγα appears first in later Greek, Refs 9th c.AD+; ἐν τῷ ω ¯ μεγάλῳ under omega (in a lexicon), Refs 2nd c.AD+

H. G. Liddell, R. Scott, H. S. Jones, A Greek-English Lexicon (9th ed., 1925–1940) — digitised by the Perseus Digital Library and corrected and expanded by Tyndale House, Cambridge, via STEPBible-Data's TFLSJ table, CC BY 4.0. Covers all of Greek literature, not just the Bible.