What term is used for the letter "O" in the phonetic alphabet?

The term used for the letter "O" in the phonetic alphabet is "Oscar." This terminology is part of the NATO phonetic alphabet, which assigns specific words to each letter to enhance clarity, especially in communication situations like military operations or aviation where miscommunication can lead to significant errors. Using "Oscar" for "O" helps ensure that listeners understand the letter being referred to, regardless of potential background noise or differences in pronunciation. Other options such as "Orange," "Oreo," and "Olympus" do not belong to this standardized alphabet and would not be recognized in that context.