Armed sailing ship (3-2-3)
I believe the answer is:
man-of-war
'armed sailing ship' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for man-of-war that I've seen before include "Portuguese --, jellyfish" , "Old naval ship" , "A battleship - for a fighter?" , "Armed sailing ship" , "Fighting ship" .)