Which title represents a senior officer commanding a fleet?

The title of Admiral accurately represents a senior officer who commands a fleet. In naval hierarchy, an Admiral is a high-ranking officer who typically has significant authority over large groups of ships and naval operations. This rank is often associated with strategic leadership and making critical decisions that affect multiple vessels and crew members, thus distinguishing it from lower ranks.

The term Fleet Admiral, while also referring to a senior naval rank, is a designation that is generally used during wartime or significant conflict situations and is not as commonly employed in peacetime organization. A Colonel is a land-based military rank and is not applicable to naval command structures. Similarly, the title of Captain, while respected, usually refers to officers who command individual ships rather than entire fleets. Therefore, Admiral is the most appropriate title for commanding a fleet due to its established position within naval command structures.