The French ship is definitely a 'she (4)
I believe the answer is:
lass
''she' is the definition.
(I've seen this before)
'the french ship' is the wordplay.
'the french' becomes 'la' ('the' in French).
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'la'+'ss'='LASS'
'is definitely a' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for lass that I've seen before include "Damsel" , "Young woman (-. Eng.)" , "Miss" , "Girl (of Richmond Hill?)" , "Sweet resident of Richmond Hill?" .)