HQ of the French vessel (5)
I believe the answer is:
depot
'hq' is the definition.
(depot can mean a military headquarters)
'the french vessel' is the wordplay.
'the french' becomes 'de' (I've seen this in other clues).
'vessel' becomes 'pot' (type of container).
'de'+'pot'='DEPOT'
'of' is the link.
(Other definitions for depot that I've seen before include "Opted (anag)" , "Headquarters - storehouse" , "Toped (anag.)" , "Supply base" , "Military HQ" .)