the.com/rear admiral

Senior enough to have a flag, junior enough to still answer to someone.

means A naval officer rank just above commodore and below vice admiral, typically commanding a group of ships or a sector of fleet operations.

from From the old practice of dividing a fleet into three divisions for battle: vanguard, center, and rear. The admiral commanding the rearmost squadron was, literally, the 'rear admiral' — the junior of the three admirals (rear, vice, and the full admiral commanding the center). The 'vice' in vice admiral comes from the same scheme, commanding the van, or front.

origin
Commanded the rear ships of a fleet line
rank tier
One star below vice admiral, two below admiral
navy quirk
Split into upper and lower half grades
first use
Dates to 17th century British naval hierarchy
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