What does the abbreviation RDML stand for?

The abbreviation RDML stands for Rear Admiral Lower Half, which is a specific rank within the United States Navy and Coast Guard. In naval ranking, the designation of "Rear Admiral Lower Half" represents a one-star admiral, which is a senior officer above the rank of Captain but below that of a Rear Admiral Upper Half (a two-star admiral). This rank is notable not only for its position within the hierarchy of naval ranks but also for its responsibilities, which can include commanding naval groups or serving in significant staff positions.

Understanding this rank is crucial for those involved in naval operations or management, as it indicates the level of authority and leadership expected of an officer holding this title. The other options presented do not correspond to any recognized naval rank or terminology, making the choice of Rear Admiral Lower Half the only accurate selection.