Hurry to join mums in the club (6)
I believe the answer is:
mashie
'club' is the definition.
(type of golf club)
'hurry to join mums' is the wordplay.
'hurry' becomes 'hie' (historical word meaning go quickly or hasten).
'to join' says to put letters next to each other.
'mums' becomes 'mas' ('ma' can be a synonym of 'mum').
'hie' put after 'mas' is 'MASHIE'.
'in the' acts as a link.
(Other definitions for mashie that I've seen before include "One of 9 [CLUBS]" , "He aims (anag) - golfer's five iron, formerly" , "Old-fashioned golf club" , "Old golf club" , "Golf club for lofting" .)