Fool European singer (5)
I believe the answer is:
twite
'singer' is the definition.
Both the answer and definition are singular nouns.
Perhaps they are linked in a way I don't understand?
'fool european' is the wordplay.
'fool' becomes 'twit' (I've seen this before).
'european' becomes 'e' (abbreviation e.g. EU).
'twit'+'e'='TWITE'
(Other definitions for twite that I've seen before include "18's [BIRD]" , "Bird's name" .)