Soldier to position around Western Front (5)
I believe the answer is:
sweat
'soldier' is the definition.
(thesaurus)
'position around western front' is the wordplay.
'position' becomes 'seat' (seating is a kind of positioning**).
'around' indicates putting letters inside.
'front' indicates taking the first letters.
The first letter of 'western' is 'w'.
'seat' enclosing 'w' is 'SWEAT'.
'to' is the link.
(Other definitions for sweat that I've seen before include "Salty fluid secreted by glands" , "Waste (anag.)" , "(Of argument) intense" , "Perspire" , "It's hard work" .)