What does O mean in English?

O is the fifteenth letter of the English alphabet. O is used to mean zero, for example when you are telling someone a phone number, or mentioning a year such as 1908. O is used in exclamations, especially when you are expressing strong feelings. O how mistaken you are! O God, I want to go home. 4. See also oh 5.

What does O mean in Greek?

The letter was adopted with the value in the Old Italic alphabets, including the early Latin alphabet. In Greek, a variation of the form later came to differentiate this long sound (omega, meaning "large O") from the short o (Omicron, meaning "small o"). The Greek omicron gave rise to the corresponding Cyrillic letter O.

Is O a word or a noun?

"O" in isolation is a word, also spelled "oh" and pronounced /oʊ/. Before a noun, usually capitalized, it indicates direct address (the vocative case), as in the titles "O Canada" or "O Captain! My Captain!" or in certain verses of the Bible.