A refusal from the French soon (4)
I believe the answer is:
anon
'soon' is the definition.
(synonyms)
'a refusal from the french' is the wordplay.
'refusal from the french' becomes 'non' (I am not sure about this - if you are sure you should believe this answer much more).
'a'+'non'='ANON'
Can you help me to learn more?
(Other definitions for anon that I've seen before include "soon to be written" , "Well-published writer" , "prolific author" , "Of unknown identity, in short" , "Soon; unattributed" .)