Some variation in pocket money (6)
I believe the answer is:
change
This clue is a double definition.
'some variation' is the first definition.
(thesaurus)
'pocket money' is the second definition.
(I've seen this in another clue)
'in' acts as a link.
(Other definitions for change that I've seen before include "It may be small" , "Coppers, perhaps" , "Alter the money returned" , "Coins of low value" , "It's said to be as good as a rest" .)