Old sailing vessel (7)
'old sailing vessel' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for galleon that I've seen before include "Ship of the line" , "Spanish treasure ship" , "Large old sailing vessel" , "Large old square-rigged sailing ship" , "Old Spanish ship" .)
(Other definitions for caravel that I've seen before include "small boat" , "Spanish ship" .)