Flotilla (6)
I believe the answer is:
armada
'flotilla' is the definition.
(I have seen 'Large flotilla' mean 'armada' so perhaps 'flotilla' could also mean 'armada')
This is the entire clue.
(Other definitions for armada that I've seen before include "Fleet of armed ships" , "Large flotilla" , "Old Spanish fleet" , "The Spanish force" , "A great fleet of warships" .)