noun U.S. Navy.
the highest ranking naval officer, ranking next above admiral.
Origin of fleet admiral
First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for fleet admiral
an officer holding the most senior commissioned rank in the US and certain other navies
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012