What is the phonetic term for the letter 'O'?

The phonetic term for the letter 'O' is "Oscar." In the context of the International Radiotelephony Spelling Alphabet, commonly known as the NATO phonetic alphabet, each letter is represented by a unique word to ensure clarity and avoid confusion during verbal communication. The term "Oscar" is specifically designated for the letter 'O,' making it widely recognized and used in various fields, including aviation and maritime communication.

Other terms like "Olive," "Orange," and "Ombra" do not represent 'O' in the phonetic alphabet and therefore are not suitable for this context. "Oscar" ensures clear communication and understanding, which is particularly crucial in situations where miscommunication could lead to serious consequences.