"Fernando” singers (4)
I believe the answer is:
abba
'fernando singers' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for abba that I've seen before include "rhymes in Petrarchan sonnet" , "Waterloo singers" , "camel-hair coat" , "Biblical father" , "Enclosed rhyme" .)