Last from risque joke stock (5)
I believe the answer is:
equip
'stock' is the definition.
(thesaurus)
'last from risque joke' is the wordplay.
'last from' indicates one should take the final letters.
'joke' becomes 'quip' (quipping is a kind of joking).
The final letter of 'risque' is 'e'.
'e'+'quip'='EQUIP'
(Other definitions for equip that I've seen before include "Provide stuff" , "Supply with what is needed" , "Provide with kit" , "Provide with stock" , "Outfit" .)