What title is used for the O-10 military rank?

The title used for the O-10 military rank is Admiral. This designation is specific to the naval and maritime services in the United States military, indicating a senior level of command. An Admiral typically oversees significant naval operations and has authority over multiple naval forces.

The title of Fleet Admiral, while it also represents a rank higher than Admiral, is a rare four-star rank that has only been used during wartime and is not in common usage. General is the O-10 rank in the Army, Air Force, and Marine Corps, which signifies a top command position in those services, but it does not apply to naval forces. Colonel, on the other hand, is a much lower rank (O-6) and is not applicable to the discussion of O-10 ranks. Thus, Admiral is the correct title for the O-10 rank in naval contexts.