"Money, Money, Money" group
I believe the answer is:
'money money money group' 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 "Group winning the 1974 Eurovision Song Contest in Brighton" , "striped coat?" , "Swedish artists" , "Coptic bishop's title; Swedish pop group" , "Enclosed rhyme" .)