The lad's in a sort of club that's tacky (8)
I believe the answer is:
adhesive
'tacky' is the definition.
(I've seen this in another clue)
'the lad's in a sort of club' is the wordplay.
'the lad's' becomes 'hes' (I am not sure about this - if you are sure you should believe this answer much more).
'in' is an insertion indicator.
'sort of club' becomes 'dive' (dive can mean a sleazy club).
'a'+'dive'='adive'
'hes' put within 'adive' is 'ADHESIVE'.
'that's' is the link.
Can you help me to learn more?
(Other definitions for adhesive that I've seen before include "very clingy" , "Substance that sticks" , "It sticks things together" , "Tacky" , "doing some bonding" .)