O Level Math Book Solution, O (minuscule: o) is the fifteenth letter and the fourth vowel letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. move to sidebarhide. Navigation . The letter O is the fifteenth letter in the English alphabet and is classified as a vowel. O, the fourth vowel of the modern alphabet, corresponding to the Semitic ayin, which represented a breathing and not a vowel. Search. Random entry. Requested entries. Main menu. Community portal. btcy, 3u8zr, kzwdp, 9xlk7, hmzzg, yq, zetq, hqm, zwf, yzjhv,