- Among the ancients, O was a mark of triple time, from the notion
that the ternary, or number 3, is the most perfect of numbers, and
properly expressed by a circle, the most perfect figure. - One. - An exclamation used in calling or directly addressing a
person or personified object; also, as an emotional or impassioned
exclamation expressing pain, grief, surprise, desire, fear, etc. - The letter O, or its sound.
- Something shaped like the letter O; a circle or oval.
- A cipher; zero.