Armada from France shelter before start of Trafalgar (5)
I believe the answer is:
fleet
'armada' is the definition.
(thesaurus)
'france shelter before start of trafalgar' is the wordplay.
'france' becomes 'f'.
'shelter' becomes 'lee' (I've seen this before).
'before' means one lot of letters go next to another.
'start of' suggests taking the first letters.
The first letter of 'trafalgar' is 't'.
'f'+'lee'+'t'='FLEET'
'from' acts as a link.
(Other definitions for fleet that I've seen before include "Fast kind of armada?" , "ships, lots of them" , "Naval force or collection of buses" , "Body of ships" , "Ships - quick!" .)