O, or 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.

O, the fourth vowel of the modern alphabet, corresponding to the Semitic ayin, which represented a breathing and not a vowel. The Semitic form may have derived from an earlier sign representing an eye.

O definition: the fifteenth letter of the English alphabet, a vowel. See examples of O used in a sentence.

The name of the Latin-scriptletter O/o. A zero(used in reading out numbers). It is currently two-o-five in the afternoon (2:05 PM). The first permanent English settlement in America was in Jamestown in …

O is used to mean zero, for example when you are telling someone a phone number, or mentioning a year such as 1908.

O, o meaning: 1. the 15th letter of the English alphabet 2. used in speech to mean zero: 3. used when talking to…. Learn more.

Learn how to easily type O with accent marks for various languages. Enhance your typing skills today!

Dec 11, 2025 · Learn the various methods and techniques to type the letter O with an accent mark (ò, ó, ô, õ, ö) using your Windows or Mac keyboard.

3 days ago · The letters O and o take this name if they are not treated as alphabetic letters used to represent phonemes /ɔ/. For example, in geometry, "point O" is called "điểm ô", not "*điểm o".

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