They look for a singing group (7)
I believe the answer is:
seekers
'they' is the definition.
Both the answer and definition are plural nouns.
Perhaps there's a link between them I don't understand?
'look for a singing group' is the wordplay.
'look for' becomes 'seek' (synonyms).
'a singing group' becomes 'ers' (I can't justify this - if you can you should give a lot more credence to this answer).
'seek'+'ers'='SEEKERS'
Can you help me to learn more?
(Other definitions for seekers that I've seen before include "Searchers" , "Religious group" .)