Work advanced in West London (5)
I believe the answer is:
acton
'west london' is the definition.
The definition suggests a singular noun which matches the answer.
'work advanced in' is the wordplay.
'work' becomes 'act' (synonyms).
'advanced in' becomes 'on' (I can't justify this - if you can you should believe this answer much more).
'act'+'on'='ACTON'
Can you help me to learn more?
(Other definitions for acton that I've seen before include "Part of the London borough of Ealing - British historian, d. 1902" , "part of London on the tube" , "London area" , "somewhere in London" , "Gladstone's adviser" .)