Obliterate European force going to front (6)
I believe the answer is:
efface
'obliterate' is the definition.
(synonyms)
'european force going to front' is the wordplay.
'european' becomes 'E' (abbreviation e.g. EU).
'force' becomes 'F' (symbol used in Physics e.g. f=ma).
'going to' means one lot of letters go next to another.
'front' becomes 'face' (face is a kind of front).
'e'+'f'+'face'='EFFACE'
(Other definitions for efface that I've seen before include "Do away with" , "Delete, wipe out" , "Remove all trace of" , "Obliterate by rubbing out" , "The selling of goods in large quantities" .)