Victory achievable, Napoleon heads for the front (3)
I believe the answer is:
van
'the front' is the definition.
(thesaurus)
'victory achievable napoleon heads' is the wordplay.
'heads' indicates taking the first letters.
The initial letters of 'victory achievable napoleon' is 'VAN'.
'for' is the link.
(Other definitions for van that I've seen before include "Leading military units" , "Goods vehicle" , "Leading unit at the head of an army" , "Light lorry" , "Commercial road vehicle" .)