A Fleet Admiral is a generic term for a senior admiral in command of a large group of ships, comprising a Fleet or, in some cases, a group of Fleets. If actually a rank (equivalent to an army Field Marshal), it has a variety of names depending on the country, including Fleet Admiral, Admiral of the Fleet, Admiral of the Navy, and Grand Admiral.
Country specific
The following articles contain specific information on the rank as it pertains to individual countries:
The associated List of Fleet and Grand Admirals provides a summary of those who have held the rank of Fleet Admiral, or its equivalent
Other countries
The rank also exists or has existed (on paper at least) in Bangladesh, Indonesia,Nigeria, Oman, and Pakistan although not all of these countries have actually ever bestowed the rank on an individual.
Fictional
The following article contains information about fictional Fleet Admirals
Alternate Meanings