Armada ship (4)
'armada ship' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for galleon that I've seen before include "One might sink" , "Trader" , "Large old sailing vessel" , "Large Spanish sailing ship of yore" , "All gone (anag.)" .)
(Other definitions for gall that I've seen before include "Growth on tree; bile; resentment" , "Impudence - annoy" , "Brass nedk or bile" , "Bold impudent behaviour; abnormal growth on tree" , "Ill-will - bile" .)