It's pure nonsense holding Eastern money (5)
I believe the answer is:
rupee
'eastern money' is the definition.
'rupee' can be an answer for 'money' (currency of India). I am not sure about the 'eastern' bit.
'it's pure nonsense holding' is the wordplay.
'it' becomes 'e' ('e' can mean 'electronic' which is similar to 'IT').
'nonsense' is an anagram indicator.
'holding' means one lot of letters goes inside another.
'pure' is an anagram of 'rupe'.
'e' inserted into 'rupe' is 'RUPEE'.
Can you help me to learn more?
(Other definitions for rupee that I've seen before include "Unit of money in India" , "Indian currency unit" , "available without capital holds up" , "low cost in Pakistan?" , "Currency of the subcontinent" .)