Send on tablet stolen from joint (5)
I believe the answer is:
refer
'send' is the definition.
(referring is a kind of sending)
'on tablet stolen from joint' is the wordplay.
I cannot quite see how this works, but
'on' could be 're' ('on' can be mean 'with reference to') and 're' is found in the answer.
'tablet' could be 'e' (E can mean ecstasy or an ecstasy tablet) and 'e' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for refer that I've seen before include "Relate" , "Bring up" , "Draw attention" , "Consult" , "Send or direct to a specialist" .)