Jack takes him round to the club (3)
I believe the answer is:
roy
'jack' is the definition.
Both the answer and definition are singular nouns.
Perhaps they are linked in a way I don't understand?
'him round to the club' is the wordplay.
'him' becomes 'or' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'round' says the letters should be written in reverse.
'to the club' becomes 'Y' (YMCA or YWCA commonly shortened).
'or' reversed gives 'ro'.
'ro'+'y'='ROY'
'takes' is the link.
Can you help me to learn more?
(Other definitions for roy that I've seen before include "-- Hattersley; -- Jenkins" , "Rob . . . was a notorious Scottish outlaw" , "'Rob ..., ... Rogers (3)'" , "Rob . . . was a famous Scottish outlaw" , "- Orbison, US singer" .)