Military vessel, after overhaul of port, so stylish (9)
I believe the answer is:
troopship
'military vessel' is the definition.
(I've seen this before)
'overhaul of port so stylish' is the wordplay.
'overhaul of' indicates an anagram.
'stylish' becomes 'hip'.
'port'+'so'='portso'
'portso' anagrammed gives 'troops'.
'troops'+'hip'='TROOPSHIP'
'after' acts as a link.
(Other definitions for troopship that I've seen before include "Military transport vessel" , "As carrier" , "Army vessel" , "boat" .)