Supply the point before the joke (5)
I believe the answer is:
equip
'supply' is the definition.
(equipping is a kind of supplying)
'point before the joke' is the wordplay.
'point' becomes 'E' (compass point).
'before' means one lot of letters go next to another.
'the joke' becomes 'quip' (I've seen this before).
'e'+'quip'='EQUIP'
'the' is the link.
(Other definitions for equip that I've seen before include "Provide stuff" , "Furnish with requirements" , "Furnish with supplies" , "Accoutre" , "Supply (with items)" .)