The word "ooo" seems to be a typographical error or an informal expression that may not have a fixed definition. If we are assuming it is an expression of excitement or awe, it is often used as a vocal exclamation to express surprise or admiration.
The expression "ooo" likely derives from the phonetic sounds made by humans when expressing emotions such as awe or surprise. It has no formal etymology in the English language but is used in various informal contexts.