In a while, a refusal from Nancy (4)
I believe the answer is:
anon
'in a while' is the definition.
(synonyms)
'a refusal from nancy' is the wordplay.
'refusal' becomes 'no'.
'from' says to put letters next to each other.
'nancy' becomes 'n' (this might be a standard abbreviation which I don't know about).
'a'+'no'+'n'='ANON'
Can you help me to learn more?
(Other definitions for anon that I've seen before include "At another time and with no identity, in short" , "coming after a call" , "Immediately" , "At another time, of old" , "Of unknown authorship" .)