ウェブ2 日前 · the fifteenth letter of the English alphabet: from the Greek omega and omicron, both borrowed from the Phoenician. 2. any of the speech sounds that this letter represents, as, in English, the vowel ( (oʊ) ) of boat, ( (ɑ) ) of hot, or ( (ɔ) ) of wrong. 3. a type or impression for o or O. 4.