No matter which (3)
I believe the answer is:
any
'no matter which' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for any that I've seen before include "Long-running Radio 4 discussion show" , "Several" , "One (unspecified)" , "One, some, every or all without specification" , "Some; none in particular" .)