Reportedly put wine in for a particular purpose (2,3)
I believe the answer is:
ad hoc
'a particular purpose' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for ad hoc that I've seen before include "Intended for one specific matter" , "For a specific purpose - Latin expression" , "'Improvised or impromptu (2,3)'" , "as required" , "(Of group) formed for one purpose only" .)